Clitic climbing (or lack thereof) and the Copy Theory of Movement

Based on consideration of understudied clitic-climbing facts from Spanish and other Romance varieties, I provide a new argument for Lower Copy Pronunciation within the Copy Theory of Movement. In the main case investigated here clitic climbing unexpectedly fails to occur for morphophonological reasons. To assume that clitic climbing in such cases is impeded in the syntax by an operation at a subsequent stage (i.e., PF) would induce a serious ‘look-ahead’ problem. In order to circumvent this issue, the data are now cast as a case where syntactic movement of the clitic can take place across restructuring/clause-union contexts, with PF factors deciding to PF-privilege (i.e., pronounce) a lower copy in a non-trivial chain with the aim of salvaging a derivation that would otherwise fail. The data thus add to the vast repertoire of phenomena amenable to a lower-pronunciation account within the overarching Copy Theory.


Introduction
I investigate certain previously unnoticed facts in relation to Clitic-Climbing (CC) contexts in Spanish where the clitic cannot climb for morphophonological (i.e., P(honetic) F(orm)) reasons (including a prohibition against contiguous identical clitics; see the series of papers on Heggie & Ordóñez 2005), as in (1). (1) a. *Se se quedó mirando en el espejo. cl.refl cl.acc stood looking in the mirror b. Se quedó mirandose en el espejo. cl.refl stood looking-cl.acc in the mirror 'S/he stared at himself/herself in the mirror.' Based on such cases, I provide a new argument for Pronounce Lower Copy/Lower Copy Pronunciation, a mechanism available as part of Chomsky's (1995; Copy Theory of Movement. According to the Pronounce-Lower-Copy proposal, a violation (in this case, a violation of the restriction that bars certain clitic clusters, such as identical clitic forms in Spanish) can be circumvented by phonologically realizing a lower copy of a member of a movement chain (i.e., X(P) … X(P)). Thus, I argue that the Pronounce Lower Copy strategy in cases like (1)b privileges the low copy of the clitic in PF in order to void the problem that would arise in the PF representation due to pronouncing the same two clitic forms adjacent to each other, as would be the case in (1)a. By contrast, no issue arises provided that the second clitic is lexicalized in its base position, as in (1)b. Therefore, Pronounce Lower Copy adds to the range of repair operations (which include salvaging strategies such as spurious Glossa general linguistics a journal of Villa-García, Julio. 2019. Clitic climbing (or lack thereof) and the Copy Theory of Movement. Glossa: a journal of general linguistics 4(1): 84. 1-19. DOI: https://doi.org/10.5334/gjgl.965 Villa-García: Clitic climbing (or lack thereof) and the Copy Theory of Movement Art. 84, page 2 of 19 se) saving derivations that would otherwise fail because of illicit clitic combinations (e.g., sequences of adjacent homophonous clitics: *se se, although I show that violations caused by other impossible clitic clusters are circumvented via Pronounce Lower Copy as well). The proposal has important theoretical consequences and yields a variety of welcome results, such as avoiding the need to incur a severe 'look-ahead' problem that would arise under the alternative analysis wherein CC does not occur in the syntax in cases like (1) because a later PF requirement would prevent certain clitic combinations. As Bobaljik (2002: 198) puts it, "operations in one component cannot 'look ahead' to be decided by factors at a subsequent stage." The approach to be defended here has the additional virtue of allowing PF to alter word order without assuming PF movement. 1 I also look at cases beyond homophonous clitics and at potential extensions to other Romance varieties.
The paper is organized as follows: in Section 2 a brief review of (non-)clitic climbing and the major formal accounts of the phenomenon are presented, including the principal data point discussed here; in Section 3, the ingredients of the analysis pursued in this paper are laid out; in Section 4, the analysis is applied to CC environments such as (1) and to additional contexts; Section 5 concludes the paper.

Clitic climbing
A prototypical case of clitic climbing is furnished in (2), which features the modal verb deber 'must.' In CC, a clitic that is generated as an object of the lowest predicate appears as a proclitic of the highest verb. As shown by the English paraphrase, the two contrasting sentences are equivalent in meaning. The literature on CC has by and large failed to find any interpretive differences between (2)a and (2)b, suggesting that CC with modals like deber 'must' is optional. 2 I turn to non-CC cases below. 3 (2) a. Debo llamarlo. must call-cl.acc b. Lo debo llamar. cl.acc must call 'I must call him.' This phenomenon has attracted much attention in the Romance literature for more than four decades. From a theoretical viewpoint, two major analyses have been pursued which assume movement −climbing-of the clitic. 4 On the one hand, Rizzi (1976;1982), Wurmbrand (2001), and Cinque (2004) champion the one-clause or restructuring view wherein the predicates involved (deber + llamar in (2)b, for example) form a combined, complex predicate or periphrasis (i.e., the infinitive and the inflected modal are reanalyzed as a unique head). Hence, the relevant cases are monoclausal (no intermediate CP occurs between the predicates). CC is therefore interpreted as an instantiation of the transparency effects stemming from clause union (see Section 4).
On the other hand, the view established by Kayne (1975;1989) is that CC involves two clauses (i.e., biclausality), with a CP being projected in between the two verbs. As Ordóñez (2013) points out, independently of which of the two analyses turns out to be 1 In this line of research, as argued by Bobaljik (2002), among others, the claim is that all movement takes place overtly in the syntax, the choice of copy to pronounce being a PF decision. 2 Gallego (2016) takes up the issue of surface semantic effects in CC. 3 I put aside here cases of obligatory CC with periphrastic tenses formed with haber 'to have' in Spanish (see, e.g., Roberts 2010). 4 For non-movement accounts, see, e.g., Sportiche (1998). correct, their common denominator is that clitic movement instantiates head movement (though see Matushansky 2006: 84 for the claim that clitics move as maximal (XP) projections but adjoin as heads (Xº)).

Non-clitic climbing contexts
Clitic climbing does not always exhibit the type of free variation illustrated in (2). In what follows, I will make reference to various contexts in which CC is impeded, and finish this subsection by concentrating on the main data point of this squib.
First, it is well known that there is a great deal of dialectal variation with regard to the phenomenon in question. In the Romance languages spoken in the North of Italy, for instance, clitic climbing is generally banned, in contrast to what happens in the South. Hence, while the (standard) Italian spoken in Northern Italy favors non-clitic climbing, the Italian spoken in the South typically opts for clitic climbing instead (see, among others, Kayne 1992; 2013 for empirical evidence). For Spanish, RAE-ASALE (2009: 1235 notes that clitic climbing is more robust in speech and in informal registers (on the issue of variation, see Cinque 2006 andSitaridou et al. 2015).
Leaving aside variation for the time being, it is also the case that certain intervening elements, such as adverbs, complementizers, negation, and most prepositions, tend to block climbing (see Ordóñez 2013 and Gallego 2016 for evidence; see RAE-ASALE 2009: 1239 for exceptions). One illustrative example is the well-known contrast in (3), which includes the verb querer 'want' plus an infinitive −a quintessential CC environment. Here, the presence of the negation between the inflected verb and the infinitive causes the clitic lo to stay low.
want not buy-cl.acc 'I want to not buy it.' This type of evidence has been brought to bear on different issues, depending on the theoretical perspective adopted. On the one hand, for those advocating that clitic climbing is the result of restructuring in a clause-union environment, the presence of the negation would disrupt the necessary relationship between the inflected verb and the infinitive, thus breaking the verbal complex characteristic of monoclausal sentences and, in turn, disallowing transparency effects such as clitic climbing. Alternatively, for those who assume biclausality in cases like (3), the presence of no impedes movement of the clitic to the inflectional head Tº. Thus, such data have been taken to be an argument in favor of the movement analysis of clitics, as they display sensitivity to locality constraints on movement. Similarly, with certain predicates, such as causatives, clitic climbing in Spanish is subject to a poorly understood but well-documented animacy restriction, due to which animate clitics cannot appear with the high verb (Fernández-Soriano 1999;RAE-ASALE 2009;Ordóñez 2013). 5 This is exemplified in (4)a, where the low clitic is an animate (more 5 As pointed out by an anonymous reviewer, it seems that this has to do with the feature [+human] rather than with animacy in general, in such a way that if the climbed clitic refers to an animal, the examples improve, at least in this referee's dialect. I concur with this judgment. Similarly, a different referee notes that this restriction has been reported to apply in many dialects (but not in mine) in non-CC contexts with canonical datives, as in (i): (i) a. Le enviaron un coche / un fontanero. cl.dat sent a car a plumber 'They sent him a car / a plumber.' Villa-García: Clitic climbing (or lack thereof) and the Copy Theory of Movement Art. 84, page 4 of 19 specifically, [+human]) direct object. This example stands in glaring contrast to (4)b, with an inanimate/[-human] one. Note that the dative clitic is an argument of the higher predicate and therefore does not originate within the lower VP, and that the non-CC versions of both sentences are perfectly acceptable (i.e., Te hizo invitarlo/comprarlo).
(4) a. *Te lo hizo invitar. cl.dat cl.acc [+human] made invite 'S/he made you invite him.' b. Te lo hizo comprar. cl.dat cl.acc [-human] made buy 'S/he made you buy it.' Lastly, the novel case that this squib is concerned with, exemplified in (1) and illustrated again by the examples in (5), is particularly interesting because contrary to what happens in (4), it displays no animacy restriction. 6 This is straightforwardly corroborated by (6)a, where the CCed direct object clitic lo is coreferential with a preverbal [+human] direct object. Thus, although a problem clearly arises in (5)a, the issue cannot be animacy, unlike in (4)a.  The periphrastic case of quedarse + -ing verb is considered by RAE-ASALE (2009: 2211 to be a semi-lexicalized construction, since quedarse in this context strongly tends to cooccur with the -ing verbal forms mirando 'looking' and viendo 'seeing.' 7 The configuration is said to be frequent in areas such as Mexico, Central America, and the Caribbean, espeb. Se lo / ?? lo enviaron. spurious se.dat cl.acc / cl.acc sent 'They sent it to him.' / 'They sent him to him.' Ormazabal & Romero (2007) relate this restriction to the Person-Case Constraint, and is active even when there is just one clitic: (i) ?? Lo hizo invitar. / Lo hizo archivar. cl.acc made invite cl.acc made file 'S/he made them invite him.' / 'S/he made them file it.' 6 As Ana de Prada (p.c.) notes, the clitic can of course also be [-human] in quedarse + -ing V contexts with and without CC. 7 An anonymous reviewer rightly observes that CC in this context is confined for most speakers to the reflexive version of quedarse, its non-reflexive homolog rejecting climbing of the lower clitic, as shown by (i): (i) ? *Y en mi casa la quedé mirando. and in my house cl.acc stood looking Intended meaning: 'I stared at her at home.' cially with the accusative forms le/les (see below), although it is also found in other parts of the Spanish-speaking world, such as Spain. 8,9 In the next section I introduce in some detail the ingredients necessary for the analysis of the contrasting examples in (5)a and (5)b to be pursued here.

The Copy Theory of Movement
One of the hallmarks of the transformational generative paradigm is the assumption that a syntactic derivation involves movement operations −transformations. For instance, in a sentence where the time of the event is questioned, this constituent is expressed by means of a wh-item (typically when) which appears at the beginning of the sentence via the displacement property, also known as movement (or internal merge/re-merge, as in Chomsky 2001 et seq.). In early conceptions of the generative paradigm, operations moving constituents were assumed to leave a t(race) generated by movement in the base position, as in (7).

(7)
When i did you become fascinated with clitic climbing t i ?
With the advent of the Minimalist Program for Linguistic Theory (Chomsky 1995 et seq.), Trace Theory was replaced by the Copy Theory of Movement (CTM), primarily for empirical reasons (see, e.g., Bošković & Nunes 2007). According to this proposal, movement is a composite operation that involves copying and deleting, as in (8). 10 (8) When did you become fascinated with clitic climbing when? 10 This indicates that the structure that creates the necessary environment for CC is only the reflexive option. However, the following piece of spontaneous data from Asturian Spanish suggests instead that for some speakers proclisis of the low clitic is possible even if the high one is lacking, as shown by (ii)a. With the (singular and plural) third-person of the low accusative clitic, by contrast, the high clitic seems to be required if the low one appears proclitically, as indicated by (ii)b. Carmen Parafita Couto (p.c.) reports the same judgments in her Galician Spanish.
(ii) a. ¡Y me quedó mirando con la cara pálida! and cl.acc stood looking with the face pale 'S/he stared at me with a blank face.' b.
¡Y *(se) lo quedó mirando con la cara pálida! and cl.refl cl.acc stood looking with the face pale 'S/he stared at him with a blank face.' Further research will need to ascertain if we are dealing with an actual dialectal split here or whether this is just an issue with the third-person, as the reviewer's example in (i) involves the third person. 8 In fact, a simple corpus search (CREA) shows that the pattern is used with different persons and clitic combinations throughout the Spanish-speaking world. Incidentally, according to a search performed using the diachronic corpus CORDE, this pattern became more frequent in the 1950s. 9 As noted by an anonymous reviewer, it is interesting that an ethical dative in this context is possible even when the lower clitic still does not climb, as in (i). Note that the presence of the ethical dative does not change the status of the sentence, where the low se needs to remain to the right of its predicate, as in (i).

(i) Se
[me] quedó mirándose en el lago. cl.refl cl.ethical dat stood looking-cl.acc in the lake 'S/he, my baby, stared at him/herself in the lake.' Based on other cases of ethical datives, which show that this element occurs between the dative and the accusative (e.g., te DAT [me] lo ACC ), climbing of the low se would result in the three-member cluster se me se (e.g., *se [me] se quedó mirando en el lago) which is deemed ill-formed by all the consultants asked, perhaps partially motivated by the substandard, marginal status of me se forms. In principle, however, one would a priori expect that [me] would disrupt the fatal adjacency between se se, improving the sentence, contrary to fact. The issue seems to be more complex, and it is my hope that future research will tackle this matter. 10 Copies of moved elements are identical to each other, but the system normally realizes only one copy of a moved element. Subsequently, even though copies of a moved element are duplicates of each other, the difference between them lies in PF realization. A point of detail here is that deleted (i.e., unpronounced) copies are conventionally represented by means of <angle brackets> or strikethrough, the latter of which will be adopted henceforth: (i) When did you become fascinated with clitic climbing <when>/when? Villa-García: Clitic climbing (or lack thereof) and the Copy Theory of Movement Art. 84, page 6 of 19 The different copies create a non-trivial chain, that is, a chain that is formed by movement. The head of the chain is the highest element and its tail is the element in the base position.
A question which immediately arises in the wake of our brief outline of the CTM proposal is why it is the highest copy of a movement chain that tends to get overtly realized. The following quotation by Bošković (2001: 125) provides a natural answer to this question: Why is there a preference for pronouncing heads of chains? We can think of this as phonology trying to be "faithful" to syntax by reflecting syntactic movement whenever it can. In slightly different terms, the system is trying to provide evidence for (overt) syntactic movement. An obvious way of doing this for phonologically overt elements is to pronounce them in the moved position.
Put another way, movement must in principle be detectable (see also Trinh 2001). Accordingly, Nunes (2004) and Roberts (2010) make the related claim that not all copies can be deleted, given the principle of recoverability of deletion.
Crucially, however, there are cases in which the highest copy is not PF-realized, as will be shown in relation to Romanian multiple-wh-fronting in the following subsection.

Pronounce Lower Copy/Lower Copy Pronunciation
Despite the general preference to privilege the highest copy created by movement in PF, a sizeable body of research has shown that on occasion, a non-high copy in a movement chain has to be pronounced in order for the derivation to be convergent. In other words, there are cases when phonologically realizing the leftmost copy causes a problem in PF; nonetheless, this issue can be sidestepped by favoring a different, lower copy (i.e., by pronouncing the element in question in a different position), while keeping movement in the (narrow) syntax.
A number of works have offered a host of empirical arguments from different constructions and from different languages to this effect, including cases of A-movement, A-bar movement, head movement, and remnant movement (e.g., Bobaljik 1994;2002;Pesetsky 1997;Franks 1998;Bošković 2001 et seq.;Nunes 2004;Reglero 2004;Bošković & Nunes 2007;Kandybowicz 2008;Saab 2008;Villa-García 2013; in press; see also the collection of papers in Corver & Nunes 2007). The operation in question has been dubbed Pronounce Lower Copy (PLC) or Lower Copy Pronunciation (LCP). The strong version of PLC (Franks 1998) would have it that a low copy in a movement chain can only be pronounced if convergence so demands (i.e., if pronouncing the head of the chain causes a problem). Thus, the requirement to realize the highest copy of a non-trivial chain can be overridden iff the derivation fails in the event that the PF realization of the highest copy takes place. On this view, PLC is a last-resort operation effected to save a derivation that would otherwise crash.
One of the most compelling arguments for PLC comes from the behavior of wh-phrases in Romanian, a multiple-wh-fronting language (Bošković 2001;2002;Bošković & Nunes 2007). In questions involving more than one question word, all the wh-phrases are normally fronted to the preverbal field. This is shown by (9). By the same token, if the requirement that all wh-phrases in multiple-wh-questions be fronted in this language holds, one would expect all of the wh-phrases in a question to Villa-García: Clitic climbing (or lack thereof) and the Copy Theory of Movement Nevertheless, in contrast to (9), the question in (10) is unacceptable for most native speakers, as it creates an issue vis-à-vis phonologically identical forms, which are barred (*ce ce). 11 Can the meaning of (10) be expressed at all in Romanian? In other words, how does the system avoid the problem induced by (10)? Bošković (2002) shows that in cases like this, the object wh-phrase, ce, must appear postverbally. Put differently, ce seems to stay postverbally in a low position (i.e., as if it had not undergone movement to the preverbal field). This is indicated by (11), which is the grammatical counterpart of (10). There are in principle two options for the derivation of (11). One is to assume that the relevant wh-constituent does not move to the left of the clause, despite evidence that whphrases ordinarily front in Romanian, as shown by (9) above: (12) ce 1 V ce 1 ce 2 ?
In contrast, the reason for the putative absence of movement in this case seems to be morphophonological in nature, as has been noted, which begs the question of why the syntax would care about factors that pertain to PF. The analysis in (12), simplified by only showing the derivation of the constituents that are directly relevant to our discussion, would suffer from an acute 'look-ahead' problem, as ce 2 would not move so as to avoid a problem arising only once the derivation reaches PF. Following Bošković's (2001) lead, the other derivational possibility is to assume instead that syntactic movement in (11) actually takes place, in compliance with the requirement that all wh-phrases move in Romanian, as in (10)/(13). Critically, however, a problem ensues in the PF component if the highest copies of the moved wh-phrases are pronounced together (cf. (10)), as represented schematically in (14). 12 (13) ce 1 ce 2 V ce 1 ce 2 ?
(14) ce 1 ce 2 V ce 1 ce 2 ? (PF = û -*ce ce) Instead, this is one instance in which the system can −and in fact must-choose a low copy of a moved element in order to bypass a violation. This PLC-based analysis is shown in (15), which illustrates the simplified derivation of (11).
11 There may be dialectal variation in this regard, as four speakers from different parts of Romania actually accept (10) in spite of (what they intuitively refer to as) the cacophonic nature of the ce-ce sequence (Bošković 2001 also notes that some of his native-speaker consultants lack the relevant constraint). I would like to thank Alexandru Giurgea for bringing this to my attention. 12 As argued extensively by Bošković (2001), there is a filtering effect of PF on syntax. See Bošković & Nunes (2007) for evidence that movement of ce 2 does indeed occur.
(15) ce 1 ce 2 V ce 1 ce 2 ? (PF = ü -ce V ce) Therefore, (11) is an illustration of the intricate interaction between syntax and morphophonology, with a PF requirement taking precedence over a syntactic one. Contra the previously outlined account (cf. (12)), the PLC analysis solves the issue posed by (10) without making changes to the syntax of multiple-wh questions, without appealing to PF movement, and importantly without incurring a rather theoretically unappealing 'look-ahead' problem. As a result, the PLC alternative in (15) is preferable to the account in (12).
With special reference to Spanish and other Romance languages, Villa-García (2013; has extended this type of analysis to account for the notorious contrast in (16)a and (16)c, assuming that subjects are also amenable to a CTM account (Stjepanović 1999;Ortega-Santos 2006;Boeckx & Gallego 2008 On this view, pronouncing a high copy of the subject, as in (16)b, would lead to an ill-formed outcome in PF (Zubizarreta 2012 actually attributes the ungrammaticality of (16)a to phonological reasons). This problem vanishes if a low copy of the subject is PFprivileged, as in (16)d, which is the derivation of the grammatical counterpart of (16)a, given in (16)c. 13 In the next section, I argue that the novel facts presented in this squib regarding CC constitute further evidence for the CTM, and in particular for PLC.

Clitic climbing restrictions in Spanish: A novel argument for Pronounce Lower Copy
Returning to the basic CC contrast in (5), repeated here in (17), one may be tempted to conclude that the sole culprit of the ungrammaticality of (17)a is the presence of two phonologically identical forms (i.e., *me me). Me quedé mirándome fijamente. cl.refl stood looking-cl.acc fixedly 'I stared at myself fixedly.' However, as (18) shows, the issue seems to be morphophonological −not just phonologicalin nature, as other clusters like *me te are also excluded.
(18) a. *Me te quedé mirando fijamente. cl.refl cl.acc stood looking fixedly 13 Incidentally, postverbal subjects in non-questions tend to be instances of new information (foci), which is not the case in (16)c,d, where the subject is forced to surface postverbally owing to the presence of the preposed wh-word. See Villa-García, in press, for an analysis along these lines to account for negative infinitival imperative clauses displaying clitics in different Spanish varieties. b. Me quedé mirándote fijamente. cl.refl stood looking-cl.acc fixedly 'I stared at you fixedly.' As is well known, for instance, *me 1.SG te 2.SG is not a licit clitic cluster in Spanish (Fernández-Soriano 1999;RAE-ASALE 2009;Ordóñez 2012;Ormazabal & Romero 2015, and references therein). 14 The data also point to the conclusion that what matters is adjacency, not factors such as non-interpretability of co-occurring forms, for instance, as the counterpart of (18)a where me and te are apart from one another is a perfect outcome (cf. (18)b; see also (17)b). 15

Moving clitics
A first assumption that seems natural and well justified on independent grounds is that Romance CC involves movement of at least one clitic from its base position in the VP (i.e., its canonical postverbal object position) to the TP domain (Kayne 1975;1989;Roberts 2010, inter alia. Ordóñez 2013 offers various arguments militating in favor of the movement of clitics with particular reference to Spanish clitic climbing; see also Boeckx &Gallego 2007 andGallego 2016). In this connection, Spanish provides direct evidence that there are various positions for the clitic in CC environments, for the same clitic can occur concurrently in different positions in some speakers' colloquial speech, as well as in varieties such as Chilean Spanish (RAE-ASALE 2009: 1234; Mann 2012; González-Urzúa 2016). This is illustrated in (19) The standard assumption is that clitics that appear in proclitic positions with inflected verbs are heads that incorporate (or head adjoin) to the left of the host (Roberts 2010, inter alia). 17 A run-of-the-mill case of proclisis would be analyzed as follows, where I take 14 The specific pattern this squib focuses on allows the following CL 1 + CL 2 sequences: a first-person clitic with a third-person one (

me lo(s)/le(s)/la(s)); a second-person clitic with a first-person (te me) and a third-person singular one (te lo(s)/le(s)/la(s)); a third-person clitic with a clitic marked for any person (se me/te/lo(s)/ le(s)/la(s)/nos/os); a first-person plural clitic with a third-person one (nos lo(s)/le(s)/la(s)); and a secondperson plural clitic with a first-person plural clitic and a third-person one (os nos/lo(s)/le(s)/la(s)).
Whereas combinations of the first with the second person are illegitimate, as shown by (18)a, a combination of the second with the first is fine. Although the paradigm is not the same as the Person-Case Constraint, impossible combinations of this sort are also ameliorated by the PLC mechanism argued for here (e.g., (18)b; see also fn. 22 for cross-linguistic support for this claim). See Martins & Nunes (2017) for identity avoidance with reflexive clitics in European Portuguese. 15 Contrary to what happens in the Romanian *ce-ce case, the judgments in Spanish seem to be categorical, without variation in terms of acceptability across dialects. I would like to thank an anonymous reviewer for bringing this to my attention. As shown in Section 4.4, however, there appears to be inter-linguistic variation within Romance in this regard. 16 See Nunes (2004) on the overt realization of multiple copies. 17 Matushansky (2006) views head movement as a combination of a syntactic operation (movement) and a morphological one (m(orphological)-merger). Under this view, cliticization results from the clitic m-merging with the Vº+Tº head in the morphological component. Spanish-style V-to-T movement for granted (see, e.g., Ordóñez 2015). Note that the analysis applies to both regular proclitics and CC proclitics: 18 (20) CL+Vº+Tº For the particular CC case this paper is concerned with, which involves the pronominal verb quedarse plus an -ing form of the lower verb, recall that the highest/leftmost clitic (CL 1 ) is part of the high verb and therefore does not undergo CC, and the second or low clitic (CL 2 ) is initially merged/construed with the lowest predicate.

Obligatory CC in restructuring contexts and non-CC environments: PLC
It goes without saying that one of the main conundrums that the literature on cliticization phenomena has faced is how to explain the (apparent) optionality of CC in cases like (2). An authoritative line of research which began with the seminal work of Rizzi (1982) contends that CC is the result of a complex-predicate-formation operation that effectively creates a single clause (cf. monoclausality) (see Section 2). This process is generally referred to in the literature as restructuring (see, e.g., Wurmbrand & Lohninger 2019). Given that clitic placement is clause-bound, the fact that CC can occur across two predicates indicates that the two verbs occur in a restructured/monoclausal environment. Under this analysis, CC is obligatory because restructuring has occurred, as shown abstractly in (21). As noted above, clitics move to functional projections in the TP layer (presumably for feature-checking purposes, as in Rizzi 2000 andRoberts 2010, inter alia, though the actual motivation for clitic movement remains a topic of intensive research, as discussed by Gallego 2016, among many others). If the two verbal predicates in (21) form a unique complex predicate under clause union/monoclausality, it follows that the clitic will climb to the inflectional domain.
(21) CL V V CL On this view, in cases where the clitic does not climb, as in (2)a above and (23)b below, restructuring has not taken place, as schematized in (22).
Interestingly, although in the case at issue, which features the verb quedarse + an -ing verb, both the CC and the non-CC options seem to be readily available (cf. (23)), some speakers actually seem to favor the CC option. More specifically, two Spanish speakers, one from Valladolid and the other from Zamora, prefer the version with CC, exemplified in (23) Kayne (1992;1994) argues that in proclisis, clitics do not adjoin directly to the verb, but to a functional projection above the verb (i.e., CL+Xº Vº+Tº) (see also Rizzi 2000 andCinque 2004). 19 Future research will determine the extent of variation in this regard (see also Section 2). But even if both (23)a and (23)b are available to most speakers, the underlying derivations of the two sentences are distinct, with only the restructuring analysis triggering climbing of the clitic (cf. (21)). The alternative order in which the clitic is low (i.e., in which CC has not occurred) is thus symptomatic that restructuring has not obtained (as claimed by the representation in (22)). In other words, in non-CC contexts, the two verbs remain independent from each other, hence preventing transparency effects like CC. This is substantiated by cases like the following, where the presence of an adverb disrupts the necessary adjacency between the two verbs for complex-predicate formation to occur. As a consequence, CC is impossible and the clitic associated with the lowest predicate mandatorily remains low and surfaces as an enclitic, in contrast to what happens in cases like (23), without the intervening adverbial.
(24) a. *Me lo quedé mucho rato mirando. cl.refl cl.acc stood much time looking b. Me quedé mucho rato mirándolo. cl.refl stood much time looking-cl.acc 'I stared at him for a long time.' Significantly, in the cases that this paper focuses on, illustrated again in (25) for convenience, there is no a priori reason to assume that restructuring does not occur, since no intervening material appears to break the relationship between quedarse and mirando (cf. (25)a vs. (24)a). Recall that in principle both the restructuring and the non-restructuring derivations are possible for most speakers, in light of (23) (cf. the derivations in (21) and (22)). Me quedé mirándome fijamente. cl.refl stood looking-cl.acc fixedly 'I stared at myself fixedly.' One plausible derivation here would be to simply assume a non-restructuring context in (25), as in (22). This would automatically yield the desired outcome, (25)b, which poses no problem at all, as the clitics would never be adjacent to one another under this readily available derivational option.
Let us now look at the more interesting case, however, under the reasonable assumption that the restructuring derivation is in principle freely available in (25), as in (21). Suppose for a moment that in (25), the accusative clitic needs to remain to the right of its predicate, as in (25)b, and that the reason is that in this case, restructuring is barred. This approach poses the question of what would prevent the restructuring derivation in (25). Clearly it would be far-fetched to claim that a morphophonological issue regarding the impossibility of certain clitic combinations such as *me me would impede complex-predicate formation, in particular because one would expect restructuring to occur before clitic combinations are assessed, arguably in the PF component; this account thus also faces a 'look-ahead' problem, in analogous fashion to the account of the Romanian facts sketched in (12). Moreover, it is not at all clear why illicit clitic combinations would have a bearing on whether predicates restructure or not. Therefore, deriving (25)b by stipulating that restructuring simply cannot take place in this specific case appears to be ad hoc and does not seem to be a promising account of the absence of CC in the data at hand, notwithstanding that in principle both the non-restructuring and restructuring derivations should be available.
Let us assume then that in theory the clitic is able to move up in the syntax in (25), at least as far as the available restructured context is concerned. The reason why some clitic combinations are not legitimate has been much debated in the literature, with accounts that range from Agree-based analyses to morphological approaches. 20 Suppose then that the clitic needs to move for purposes of φ-feature satisfaction à la Roberts (2010). One approach would be to think that (i) this movement does occur, but then something happens which precludes the appearance of the clitic as a proclitic of the highest verb. An alternative would be to propose that (ii) the clitic does not move at all and stays low (i.e., it does not climb). Motivating (ii) is not obvious, since in principle the low clitic would move in order to satisfy its own features (see Bošković 2007). Furthermore, given that in such cases restructuring is in principle in place (i.e., there is no way to block clause-union syntactically), how to prevent transparency effects like clitic climbing is not apparent at all. 21 Similarly, if it is PF that rules out certain clitic combinations, as seems reasonable, the familiar 'look-ahead' problem from the Romanian case in (10)/(12) would become ostensible here as well: "an apparently syntactic operation [i.e., CC] appears to be blocked just in case it would interfere with a post-syntactic operation" (Bobaljik 2002: 200; my addition in square brackets, JVG).
Thus, let us assume that in (25)b, movement of the low clitic does take place normally, as in (25)a (cf. (i)). As soon as the syntax does its job, the structure is sent to the interfaces. Once the structure reaches PF, the system assesses whether the output of syntactic operations adheres to the well-formedness conditions of the PF component. Because certain combinations of contiguous clitics such as *me me in (25)a and *me te in (18)a are ruled out in PF, then the only procedure that the system can resort to so as to rescue the derivation at this point is to privilege (i.e., pronounce) the low copy of the clitic. This is precisely why the clitic must occur low in (18)  Recall that in this case restructuring is available, but it does not produce a legitimate output. In consequence, the derivation crashes in PF unless a salvaging strategy is employed, namely PLC. The Spanish non-CC examples in (1)b/(5)b/(18)b/(25)b are thus now cast as an environment where in principle CC is allowed to proceed syntactically, but crucially a 20 See the collection of papers on Heggie & Ordóñez (2005) for morphological approaches and for syntactic approaches to clitic combinations which assume that the morphological and phonological components act as filters (see also Bošković 2001 andBobaljik 2008 for much relevant discussion). 21 Likewise, given the ordering of clitics in the cluster, wherein the higher clitic (CL 1 ) appears to the left of the lower clitic (CL 2 ), the working hypothesis would be that the low clitic incorporates to the inflectional/verbal head before the high one. Thus, it is not clear how preventing movement of the low clitic/CL 2 to a position where it incorporates before the high clitic/CL 1 would be motivated by a problem with CL 1 , which presumably incorporates afterwards (i.e., CL 1 CL 2 quedar CL 1 + V CL 2 ). On the opposite order, CL 2 + CL 1 (e.g., me se), found in substandard Spanish varieties, see Ordóñez (2015: 259-260). Recall that the picture may be further complicated by the possible addition of an ethical dative below CL 1 , as indicated in fn. 9. In any case, it would also be possible to presume that much like dative clitics, the reflexive clitics associated with pronominal verbs like quedarse in the construction at hand move first, and then accusative clitics move, in the spirit of 'tucking in' (Anagnostopoulou 2003: 299). Yet another account would be to assume that clitics get reordered in the PF component. On the ordering of clitics more generally, see the collection of papers in Heggie & Ordóñez (2005).
low copy needs to be PF-favored in order to save a derivation, in much the same way as in the familiar Romanian case (cf. (11)/(15)). Incidentally, the copy that is privileged in PF is the same copy that is privileged in L(ogical)F(orm), as this is the clitic's base position as the object of the lowest predicate. 22 The CTM/PLC system offers a principled account of the contrast in (25) and has a number of added advantages, including the avoidance of a severe 'look-ahead' problem and the need to assume that the restructuring derivation is banned owing to putatively irrelevant (PF-related) illicit clitic clusters. The current analysis overcomes these issues and also dispenses with movement being effected in PF, the major theoretical significance of the CTM/PLC mechanism being that it enables PF to affect word order (by privileging a copy that is independently available) without having to invoke PF movement. In Section 4.4 I provide additional data from other Romance varieties in support of this approach. Before undertaking this task, however, I turn to the compatibility of the PLC system outlined here with alternative analyses of CC.

PLC and competing accounts of CC
It is important to bear in mind that the approach just sketched actually does not commit us to assuming a restructuring/clause-union account, and would in fact also be compatible with a biclausal analysis of CC à la Kayne (1975) (see also Ordóñez 2013, among others). Under this type of account, sentences where intervening material prevents the clitic from surfacing as a proclitic, as in (3)/(24), are not seen as cases where restructuring is blocked, but rather as regular structures involving two CPs where intervening material (e.g., negº no) may be a hindrance to movement operations. Accordingly, pronouncing the lowest copy of the clitic due to the presence of offending material (such as negation) would be an instantiation of the more general rescue-by-resumption approach. On this view, phonologically realizing a resumptive pronoun has an ameliorating effect with respect to locality-of-movement violations, which implies that locality is to a certain extent PF-related. Put another way, locality violations can be fixed by phonologically realizing a copy within the barrier/island as a resumptive pronoun. The availability of this rescuing strategy has been independently argued for by Shlonsky (1992), Pesetsky (1997), Bošković (2001;Nunes (2007). The approach is illustrated in (27), with the negation barring CC in cases like (3)a, whose grammatical counterpart requires the clitic to surface low (cf. (3)b).
In the particular configuration that this paper is concerned with, (26), where the issue is not triggered by a locality problem, the CTM/PLC approach would be applied in exactly the same way as under the monoclausal analysis outlined in the preceding subsection, with lower-copy pronunciation of the clitic saving a derivation that would crash on account of an ill-formed clitic cluster in PF. 23 22 Bošković (2001) provides numerous cases, especially from Bulgarian and Macedonian, where issues arising from impossible clitic combinations are fixed through PLC. Stegovec (2019) actually furnishes cases where PLC indirectly interacts with Person-Case Constraints, which resonates with my claim that it is not only phonologically identical forms that may create a problem which is then solved by selecting a lower copy in PF. 23 The biclausal analysis raises the more general question of why CC appears to be optional in regular cases.
Recall that in the monoclausal analysis, by contrast, CC occurs because of the presence of a restructured predicate coupled with the need for the clitic to adjoin to an INFL head.

Other cases amenable to PLC: Beyond Spanish
The construction consisting of quedarse + an -ing verb is not the only clitic-related pattern where a different copy of a moved clitic may be chosen for purposes of PF compliance. Other CC environments that can in principle be analyzed as involving PLC include perception verbs like those in (28) Again, *la la clusters are ungrammatical, a problem that fades away if the low clitic is pronounced in its base position as the object of cantar (cf. (28)b; V-la i la k V-la k ), in parallel fashion to what happens in (26). 24 For reasons of space, I will not delve further into these potential cases here.
Before concluding this section, reference to other (Romance) languages is in order. First, it is of note that Catalan manifests a construction akin to the main basic paradigm this squib centers upon, as shown in (29) This contrast, which is in principle also amenable to a PLC account, reveals that the pattern investigated here is not limited to Spanish.
Departing from the specific construction at issue, but still within the realm of CC, Bellinzonese, a Romance language spoken in Northern Italy, disallows two identical sa sa clitics in CC environments featuring a must-like modal, as (30)a shows. Importantly, however, the construction improves dramatically if the reflexive clitic is pronounced (i.e., PF-realized, in our terms) in its base position, as an enclitic of the lexical verb, as indicated by (30)b. 25 (30) Cattaneo (2009: 199) a. *Sa sa dev lava tücc i dì. cl.imp cl.refl must wash all the days 24 As noted by an anonymous reviewer, (28)a would be perfectly acceptable if a Rocío Jurado were a dative source. This case, exemplified in (i), is an instantiation of the so-called spurious se rule (se for le), a wellknown repair strategy in Spanish (see, inter alia, RAE-ASALE 2009).
(i) A Rocío Jurado, esa canción, me hubiese gustado oírsela cantar. 25 See Cattaneo (2009: Ch. 6) for evidence in support of the monoclausality of restructuring contexts in Bellinzonese and the relative availability of CC with duvé 'must' in this language, despite the widespread absence of CC in the Romance languages of Northern Italy (see Section 2.2). I would like to thank an anonymous reviewer for bringing Cattaneo's work to my attention.
b. Sa dev lava-s tücc i dì. cl.imp must wash-cl.refl all the days 'One must wash him/herself every day.' Such cases lend further cross-linguistic plausibility to the PLC/CTM account of the contrasts with which this paper is concerned.
Lastly, as noted by an anonymous reviewer and by Simone De Cia (p.c.), it is important to note that contiguous identical clitic forms such as se se in languages like Sovramontino, another Romance language of the North of Italy, are legitimate, as shown in (31), which is a regular clitic cluster in a non-CC environment.
(31) Se se vede. cl.imp cl.refl sees 'One sees himself/herself.' Data like (31) are compatible with the claim that the constraints that ban certain clitic sequences differ from language to language, with Catalan and Spanish observing the restriction in question, but not Sovramontino. 26

Conclusion
This squib has shown that the novel facts related to (non-)CC phenomena with quedarse + an -ing verbal form in Spanish, which exhibit certain clitic co-occurrence restrictions, are amenable to a Pronounce Lower Copy analysis within the Copy Theory of Movement, since choosing a low copy of the clitic in PF circumvents the issue that arises if the clitics are pronounced contiguously. Thus, PF has the ability to affect word order without the need to assume PF movement. The approach thus allows us to maintain movement in the syntax and is compatible with different analyses of CC and of clitic-combination restrictions. I have also shown that the analysis may be extendable to other CC-related constructions in Spanish and in other Romance varieties. Although it is by no means my claim here that all cases where a clitic cannot climb (in Spanish) can be captured under a PLC/CTM approach, it remains to be determined whether (a version of) the approach adopted here can be applied to other cases where CC cannot proceed, but where the role of PF considerations is not evident (e.g., the [+human] restriction regarding causatives in (4)). This would in principle be made possible through a filtering effect of PF on the output of syntax, much in the spirit of Bošković (2001), an issue that I leave for further inquiry. For the time being, the CC cases discussed here add to the inventory of multiple phenomena across the world's languages amenable to a Pronounce-Lower-Copy approach, hence providing further crosslinguistic support for the rather successful Copy Theory of Movement.
Abbreviations cl = clitic, acc = accusative, dat = dative, refl = reflexive, imp = impersonal, sg = singular, dom = Differential Object Marking, CC = clitic climbing, CTM = Copy Theory of Movement, PLC = Pronounce Lower Copy, LCP = Lower Copy Pronunciation, PF = Phonetic Form, LF 26 The same anonymous referee notes that the existence of data like (31) suggests that perhaps one important aspect for the approach pursued herein is that both clitics that are identical must end up in the same projection, as opposed to different projections (see also Cattaneo 2009: 200 for much relevant discussion). Thus, if clitics end up in different projections even if they are phonologically adjacent then there should be no problem. According to this reviewer, this would be the case if object clitics and subject clitics (on the assumption that impersonal se is such an element, which is not obvious) occupy different projections. Then we would expect the relevant clash not to occur and the two superficially adjacent forms to be possible, which might be the case in (31). I leave this issue for further research, granting its importance.