BUCLD 36 Proceedings
To be published in 2012 by Cascadilla Press
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Clitic Production across Tasks in Young French-Speaking
Children
Mihaela Pirvulescu, Ana T. Pérez-Leroux, Yves Roberge and Nelleke Strik
1. Introduction1"/>*
Previous research demonstrates that children acquiring French show
optionality in the realization of object clitics – and that there are therefore object
omissions – in contexts where clitic pronouns are obligatory in the target
grammar (Müller, Crysmann & Kaiser, 1996; Jakubowicz, Müller, Riemer &
Rigaut, 1997; Pérez-Leroux, Pirvulescu & Roberge, 2008; among others). Most
previous studies attribute object omissions to issues related to the domain of
verbal argument structure, that is, difficulties in realizing the clitic element or in
representing the null element associated with the clitic. Our goal is to investigate
clitic optionality in monolingual French-speaking children in order to determine
whether there are conditions on clitic optionality in children’s production, and if
there are, what the nature of these conditions is.
We focus on the syntax of clitic optionality based on a minimalist analysis
of the recoverability of silent arguments (Sigurðsson, 2011). To do so, we
contrast the results in clitic elicitation obtained in three different tasks:
indicative mood with third person subject, indicative mood with second person
subject and imperative mood with second person subject.
Our results show that clitic production varies significantly across different
elicitation tasks. We propose an explanation that reinterprets as a condition on
syntactic representations, the traditional view in acquisition according to which
children allow argument drop because they over-rely on access to discourse
(Allen, 2000).
2. Object Clitic Pronouns in French
In French, clitic pronouns are normally used to replace a previously
introduced element. For instance, the object clitic le in (1a) refers to the
* Mihaela Pirvulescu, Ana T. Pérez-Leroux and Yves Roberge, University of Toronto,
Nelleke Strik, Dalhousie University, ma.pirvulescu@utoronto.ca. We wish to thank the
audiences at Linguistic Symposium on Romance Languages 41 and BUCLD 36, as well
as H.A. Sigurðsson and the students from our Acquisition Project, Sophia Bello, Ailís
Cournane, Mélanie Elliott, Anna Frolova and Joanne Markle LaMontagne. This research
was partially supported by SSHRC grant 410-09-2026.
antecedent ce livre. Following Roberge (1990) and Sportiche (1996, 1998) we
assume that the clitic is coindexed with a null pronominal element pro, a null
object, in the canonical object position. The English equivalent in (1b) shows
that in this language a strong pronoun (it) is used in the canonical object
position.
(1) a.
b.
A: Tu veux ce livrei?
you want this book
B: Oh! Mais je li’ai
déjà
lu proi.
oh but I it have already read
A: Do you want this book?
B: Oh! I’ve already read it.
(Cummins & Roberge, 2005, p. 62)
It is also possible to drop the clitic in French (Lambrecht & Lemoine, 1996)
whereas in English a null object is not possible, as illustrated in (2). 2
(2) a.
b.
A: Tu veux ce livrei?
you want this book
B: Oh! Mais j’ai
déjà lu proi.
oh but I have already read
A: Do you want this book?
B: *Oh! I’ve already read Ø.
(Cummins & Roberge, 2005, p. 62)
Clearly, the null object in (2) has a definite anaphoric interpretation. However,
null objects in French (and English) can also have an implicit interpretation, in
which case we adopt Cummins and Roberge’s (2005) null cognate object
analysis based on work by Hale and Keyser (2002). This null object is
represented by a null Noun and an example in provided in (3).
(3) Pendant mon congé sabbatique j’ai surtout l’ intention de lire N.
During my leave sabbatical I have mainly the intent
to read
‘During my sabbatical I mainly intend to read Ø.’
(Cummins & Roberge, 2005, p. 62)
Although null objects are generally possible in adult French, certain
constructions, including imperatives, favor object omission (cf. Cummins &
Roberge, 2005 and references cited there).
2.1 Object Clitics in Child L1 French
2
How widespread clitic drop is in French still remains to be determined.
In the classic object clitic elicitation task (4), where a short story with images
precedes the prompt of the investigator (therefore introducing an antecedent), a
response with a clitic pronoun is required. Children, however, have been
observed to variably drop the clitic in this context. The alternation between the
responses in (4a) and (4b) – produced by the same child in the same type of
context – shows that clitics seem to be in free variation with null objects for
some Francophone children.
(4) a.
b.
Prompt: Dis à Kermit ce que l’ourson fait avec les framboises.
tell to Kermit what the bear does with the raspberries
‘Tell Kermit what the bear is doing with the raspberries.’
Child: Il les mange. (object clitic) (M. 3;06)
he them eats
‘He eats them.’
Prompt: Dis a Kermit ce que Sébastien fait avec le verre de jus.
tell to Kermit what Sebastian does with the glass of juice
‘Tell Kermit what Sébastien is doing with the juice.’
Child: Il boit Ø. (omission) (M. 3;06)
he drinks
‘He drinks.’
However, recent experimental studies indicate that clitic optionality might not
be totally random. First, children do not overgenerate object pronouns in the
absence of a discourse antecedent (Pérez-Leroux, Pirvulescu & Roberge 2008;
Salomo, Lieven & Tomasello, 2008). Moreover, several studies have shown that
children are sensitive to informativeness features in their patterns of argument
omission, including omission of pronominals (Allen, 2000; Allen & Schröder,
2003; Serratrice, Serrace & Paoli, 2004). Research on clitic constructions in
specific syntactic structures also shows that clitic production is drastically
limited in topicalization structures in French (Pérez-Leroux, Pirvulescu &
Roberge, 2011) or that it is boosted in island constructions in Italian (Brunetto,
2010). Finally, studying clitic production in a very controlled setting, Pirvulescu
and Hill (2011) show that rates of clitic production vary drastically across
elicitation contexts.
Various analyses have been proposed to account for clitic omission in child
language. Some proposed a deficiency specific to the clitic category
(Jakubowicz, Müller, Kang, Riemer & Rigaut, 1996; Jakubowicz et al., 1997) or
a problematic computation due to maturation (Wexler, Gavarró & Torrens,
2004) or to memory effects (Grüter, 2006). Schaeffer (1997, 2000) proposed a
pragmatic deficit as the source of omissions. An alternative view, which does
not consider omissions as the result of a deficit in either the morphosyntax of
clitics or in children’s pragmatic abilities is given by Pérez-Leroux et al. (2008),
which proposes a default null object in the early grammar. Most analyses share
the view of the clitic construction as ‘static’, and therefore do not directly
predict that clitic optionality should vary across different contexts. In contrast,
the latter view predicts sensitivity to recoverability conditions.
2.2 Background and Hypotheses
The goal of our study is to explore the effect that the syntactic and
pragmatic contexts may have on the production of object clitics in child French.
We use constructions with similar contextual linking, namely the clitic context,
but which differ in some aspect of their morphosyntax. Some evidence can be
found in previous studies on child language for the relevance of contextual
features in early argument drop. It has been proposed that informativeness
features control argument omission (Allen, 2000; Allen & Schröder 2003;
Serratrice et al., 2004). Pirvulescu and Hill (2011) showed that manipulating the
conversational context boosts clitic production to almost target-like responses.
More specifically, these authors noticed a relation between the type of
conversational setup and the rate of clitic omission: in the context of direct
address (the child addresses the interlocutor, second person subject) the rate of
object clitic omission is insignificant, while in the context of indirect address
(the child talks about a character, third person subject) the rate of omission is
considerably higher.
Following Mavrogiorgios (2009), Cardinaletti and Starke (1999) and
Déchaine and Wiltschko (2002), we analyze object clitics as phi-feature bundles
which incorporate to their verbal host. Following Sigurðsson (2011), we link the
referential silent argument (pro), associated with the incorporated clitic, to a
constituent (CLn in (5)) in the edge of the clause (the local C-domain), which
probes for a goal under Agree. Although this C/edge linking is decidedly
syntactic in nature, it interacts with pragmatics through context scanning.
(5)
CP
Sigurðsson (2011, p. 284)
Force
CLn
context scanning . . .
TP
… [phon]/ø…
C/edge linking
C/edge-linkers are logophoric (speaker and hearer) features or topical features.
Furthermore, we assume that referential null objects are available alongside with
the clitic construction in child language (Pérez-Leroux et al., 2008) and that
there is therefore a certain freedom in selecting items to Merge as direct objects
in the course of the derivation: null object with referential properties, DP, pro,
and overt pronouns (Castilla & Pérez-Leroux, 2010). Following Sigurðsson
(2011), the distribution of any silent argument is constrained by surface factors
such as lexical complementizers, agreement, etc., which can also function as
interveners between the null category and the C/edge-linkers. Within such an
approach, we could expect that features of the syntactic and/or pragmatic
context interact with clitic omission.
With this background in mind, we formulate two different hypotheses:
(6) a.
b.
H1: Clitics are optional regardless of syntactic contexts.
H2: Patterns of clitic optionality can vary across syntactic contexts.
As mentioned, previous analyses of clitic optionality in L1 French predict
experimental results consistent with H1. For instance, according to the Decayed
Features Hypothesis (Grüter, 2006), clitic drop reveals a deficit in the clitic
construction itself, and predicts uniform patterns of omission of clitics across
contexts with the same Agree distance between the clitic and the pro argument.
3. Study
3.1 Participants
Participants in our study were 16 three year-old and 17 four year-old
monolingual French-speaking children, as well as 14 adults who served as a
control group. The children were recruited from daycares in the Montreal area.
Most of the adults were daycare workers from the same daycares, while a small
number of them were relatives of one of the testers. The age range, mean age
and standard deviation (SD) for each of the groups are presented in Table 1.
Table 1. Age ranges, mean ages and SDs for participants
Age Range
Mean Age
SD
3 year-olds (n=16)
3;03 - 4;0
3;08
0;03
4 year-olds (n=17)
4;01 - 5;02
4;06
0;05
20 - 63
33
13
Adults (n=14)
3.2 Experimental task
To test the object clitic production, we used an experimental method with three
separate tasks. The context provided a definite referent, which was the topic of
the sentence prompt. The first task was a classic elicitation task for object clitics
using the indicative mood and a third person subject (cf. Jakubowicz et al.,
1996, 1997; Schaeffer, 1997 and subsequent work). In this task, the child hears
short stories accompanied by pictures. The puppet makes an erroneous statement
and the investigator invites the child to correct the puppet (see (7)).
(7) Task 1: third person subject - picture book and puppet
Prompt: Dis à Kermit ce que la fille fait avec le chariot.
tell to Kermit what the girl does with the carriage
‘Tell Kermit what the girl is doing with the carriage.’
Target clitic response: La fille le pousse.
the girl it pushes
‘The girl is pushing it.’
The second task still involved the indicative mood, but with a second person
subject (following Pirvulescu & Hill, 2011). The investigator is presenting
various toys and props to the child and is explaining what she is doing with
them. She then asks a question about it, as in (8):
(8) Task 2: second person subject - toy manipulation
Prompt: Dis-moi, qu’est-ce que je fais avec les voitures?
Tell me what
I do with the cars
‘Tell me, what am I doing with the cars?’
Target clitic response: Tu les pousses.
You them push
‘You are pushing them.’
In the third task, the subject was a second person, but was not overtly expressed,
due to the use of the imperative mood.3 In this task, the investigator is acting out
scenes with a puppet, toys, and other props. Since the puppet is made to be
somewhat distracted, the investigator invites the child to give orders to the
puppet, so that it will understand what to do. The puppet asks the child what to
do with each toy (see (9)).
(9) Task 3: Imperative- toy manipulation and puppet
Prompt: Dis-moi quoi faire avec le camion.
Tell me what do with the truck
‘Tell me what to do with the truck.’
Target clitic response: Pousse-le!
‘Push it!’
There were 12 items per task. In each task, half of the items contained a singular
referent and the other half a plural referent. Moreover the items were equally
divided between masculine and feminine referents.
To summarize, the distinction between Task 1 and Task 2 reduces to the
contrast between third person subject (indirect address) and second person
subject (direct address), whereas the difference between Task 2 and Task 3 is
essentially that between indicative and imperative mood since in both cases the
subject is a second person.
To our knowledge, this is the first experimental study of clitic production utilizing
imperatives.
3
3.3 Results
We first consider the overall results for the three tasks and the three groups.
In addition to target clitic responses, three other response types were produced:
DPs, null objects and ‘other’ responses (see (10)).
(10) a.
Clitic:
b.
DP:
c.
Null:
d.
Other:
Elle les coupe. (M. 4;03)
She them cuts
‘She’s cutting them’
Tu manges la carotte. (R. 3;11)
you eat
the carrot
‘You’re eating the carrot’
Bois! (T. 4;03)
‘Drink!’
Responses not using the target verb or verb form,
non-responses, non-relevant responses.
Responses not using the target verb form are particularly frequent in Task 3.
Instead of producing an imperative, children sometimes used infinitives or the
construction il faut followed by an infinitive (see (11)).4
(11) a.
b.
Ouvrir les bouteilles. (I. 3;0)
open
the bottles
‘To open the bottles.’
Il faut couper. (J. 3;03)
it must cut
‘You have to cut.’
Table 2 presents mean numbers and SDs in brackets. Recall that each task
contained 12 test items. Hence, the maximum number for each response type is
12. The data in this table show that clitic production fluctuates across tasks and
the rate of clitics increases between 3 year-old and 4 year-old children. At the
same time, null objects and DP’s decrease. The adults produced particularly
high rates of DPs, but clearly fewer null objects than the children.5 A mixed
design ANOVA showed a highly significant effect of both age (F(2,44)=11.75,
4 Children who produced responses such as in (11) received a second (more explicit)
prompt from the investigator, inviting them to use an imperative. This prompt indeed
yielded more imperatives, but in order to be consistent and not to mix elicitation
techniques, these responses have not been counted under imperatives in Table 2.
5 We speculate the high number of DPs is due to a task effect. In the experimental
context, the adults had a tendency to be overly correct and to literally repeat the
investigator in producing DPs instead of clitics.
p<.000) and task (F(2,43)=26.92, p<.000), but not a significant interaction.
Thus, both age and context are relevant factors in clitic production.
Table 2. Mean numbers and SDs of response types per task per group
Clitic
DP
Null
Other
Task
1
3rd p.
Task
2
2nd p.
Task
3
Imper.
3 year-olds
1.94 (2.9)
4.75 (3.2)
3.37 (3.0)
1.94 (1.3)
4 year-olds
5.06 (3.1)
3.0 (2.7)
2.53 (2.7)
1.41 (0.87)
Adults
2.71 (2.8)
9.29 (2.8)
0
0
3 year-olds
4.06 (4.1)
3.62 (3.6)
2.88 (3.6)
1.44 (1.8)
4 year-olds
8.94 (3.6)
1.23 (2.1)
1.24 (1.8)
0.59 (0.8)
Adults
3.5 (4.5)
8.14 (4.6)
0.36 (0.7)
0
3 year-olds
0.19 (0.5)
3.63 (3.2)
0.74 (1.6)
7.44 (3.7)
4 year-olds
2.35 (3.3)
2.82 (2.2)
1.18 (1.6)
5.65 (4.1)
Adults
0.5 (0.5)
9.43 (2.8)
0.14 (0.4)
1.93 (2.7)
We now take a closer look at clitic production in children across tasks
considering only relevant responses (i.e., excluding ‘other’ responses). Figure 1
shows proportions of clitics among relevant responses (i.e., clitic, DP and null)
for Task 1 and Task 2.
Figure 1. Proportions of clitics among relevant responses per group: Task 1
versus Task 2
A mixed-design ANOVA showed a main effect of Task (F(1,31)=27.73, p<.000)
and age (F(1,31)=71.45, p<.000), and no interaction. Task 1 (with a second
person subject) yields many more clitics than Task 2 (with a third person
subject). This replicates previous results obtained by Pirvulescu and Hill (2011)
although the difference in our task, while significant, is not as polarized as in
this previous study.
In Figure 2 proportions of clitics among relevant responses for Task 2 and
Task 3 are compared.
Figure 2. Proportions of clitics among relevant responses per group: Task 2
versus Task 3
Figure 2 shows that mood is also a relevant factor in clitic production. A mixeddesign ANOVA showed a highly significant main effect of Task
(F(1,31)=45.72, p<.000) and Age (F(1,31)=76.16, p<.000), and near significant
interaction (F(1,31)=3.63, p=.066). The indicative mood context with a second
person subject yields many more clitics than the imperative mood context with
an (implicit) second person subject. For imperatives, most responses were of the
DP type, but null objects were present as well. Crucially, development did not
affect the proportion of clitics/nulls in the same way as in the indicative task: 4
year-olds give comparable rates of clitic and null responses; see Figure 3 below.
Figure 3. Proportions of relevant responses per group: Task 3
The differences in clitic production between Task 1, 2, and 3 confirm
Hypothesis 2, namely that patterns of clitic optionality can be affected by the
syntactic context.
4. Discussion and conclusions
Recall our theoretical assumptions: 1) the existence of a referential null
object in child grammar alongside with the clitic option, and 2) licensing of the
referential null object through the left periphery of the clause. While most
previous studies have assumed that object omission is due to a problem within
the verb-object area, we propose that the left periphery also interferes with this
phenomenon (following, within a more articulated syntactic framework,
previous proposals by Hulk & Müller, 2000 and Hill & Pirvulescu, 2011).
We adopt Sigurðsson’s (2011) approach according to which referential null
arguments are either phi-silent (Chinese argument-drop type) or phi-overt
(Romance null subjects type). All arguments have to be C/edge linked.
However, in the case of phi-overt arguments this linking is made through the
overt phi-features, which has consequences for the recoverability of the null
argument. Specifically, a phi-overt null argument can match CLn features in the
C domain across lexical categories. For the case of French, we propose that, as
in the case of Romance null subjects, the clitic construction involves a phi-overt
null argument, with the pro as the null argument and the clitic as the overt
manifestation of the argument’s phi-features. For the case of the referential null
object, we consider that this might be a case of a genuinely phi-silent null
argument. If this is the case, then following Sigurðsson (2011), this type of null
argument is subject to intervention effects: “Radically phi-silent arguments
differ from phi-overt arguments (including Romance Ø-Tphi) in that their
C/edge linking is invisible, hence uninterpretable across a spelled-out intervener
in the C-system” (p. 270).
We propose that the following constructions are available in the child
grammar for the direct object argument:
(12) a.[CP.. X ... [TP ... Ø ... ]] = object omission
b.[CP..X … [TP ... Cl ... Ø... ]] = clitic construction
c.[CP..X … [TP ... DP... ]] = Overt DP
Construction (12a) is specific to the child grammar while constructions (12b)
and (12c) exist in both the child and adult grammars. Assuming that the default
construction in child grammar is a., this will be used unless something prevents
it. According to our results, the context of second person subject seems to
disfavor the use of the null object construction, favoring clitics instead. The
second person subject can therefore be considered a potential intervener between
the C/edge linker and the null object as in (13) and (14) below:
(13)
[CP.. X ..2Pers .. [TP ... cl-V Ø... ]]
Null object linking OK
Potential intervener (2nd person subject)
(14)
[CP..X …2Pers .. [TP ... V Ø... ]]
impossible linking of the null object
Intervener (2nd person subject)
Therefore, according to our analysis, the second person subject blocks the
C/edge linking of the null referential argument, this context resulting in a higher
use of the clitic construction. If this is the case, the null object in French early
grammar appears to be a true phi-silent null argument of the Chinese type: that
is, it has to match the C/edge features under distant agreement, as opposed to the
German type where the null object has the possibility of moving into the Cdomain. The C/edge blocking by the second person subject seems to conform to
the situation observed in Sigurðsson (2011) for Swedish, where a more specific
(subject) clitic intervenes between the silent logophoric C-features and the
clause internal null object (i.e., the Relative Specificity Constraint).
Interestingly, while our imperative task yielded few null and clitic
responses, favoring DP-responses, both clitic and null responses seem available,
in comparable proportions for 4 year-olds. Null objects are not blocked in this
context. We speculate that this is because in the imperative mood, no
syntactically (and phonologically) active second person subject features are
present (cf. Mavrogiorgios, 2009). Therefore, no intervention effects occur.
To conclude, we have shown in this paper that clitic omission in child
French is not uniform across tasks within the same modality, an elicited
production context. Some tasks generate significantly higher rates of object
clitics and have a steeper developmental curve. This shows that we cannot
consider omission as a developmental deficiency in the syntactic computation of
the clitic. We propose that omission is the result of several options available in
the child grammar, including the null referential object and the syntactic
constraints regulating its distribution. Therefore, omission is made possible
within an appropriate discourse situation, but is regulated by the syntactic
context.
References
Allen, Shanley (2000). A discourse-pragmatic explanation for argument representation in
child Inuktitut. Linguistics, 38, 483–521.
Allen, Shanley & Schröder, Heike (2003). Preferred argument structure in early Inuktitut
spontaneous speech data. In John W. Du Bois, Lorraine E. Kumpf & William J.
Ashby (Eds.), Preferred argument structure: Grammar as architecture for
function (pp. 301-338). Amsterdam: John Benjamins.
Brunetto, Valentina (2010). Syntactic diagnostics for referentiality marking in early null
objects: evidence from Italian. In Barry Heselwood & Leendert Plug (Eds.),
Leeds Working Papers in Linguistics and Phonetics 15 (pp. 1-13). Leeds:
Department of Linguistics and Phonetics, University of Leeds.
Cardinaletti, Anna & Starke, Michal (1999). The typology of structural deficiency: A
case study of the three classes of pronouns. In Henk van Riemsdijk (Ed.),
Clitics in the Languages of Europe (pp. 145-233). Berlin: Mouton de Gruyter.
Castilla, Anny P. & Pérez-Leroux, Ana T. (2010). Omissions and substitutions in Spanish
object clitics: Developmental optionality as a property of the representational
system. Language Acquisition, 17(1/2), 2-25.
Cummins, Sarah & Roberge, Yves (2005). A modular account of null objects in French.
Syntax, 8, 44–64.
Déchaine, Rose-Marie & Wiltschko, Martina (2002). Decomposing Pronouns. Linguistic
Inquiry, 33, 409-442.
Grüter, Teres (2006). Object clitics and null objects in the acquisition of French.
Unpublished doctoral dissertation, McGill University.
Hale, Kenneth & Keyser, Samuel J. (2002). Prolegomenon to a Theory of Argument
Structure. Cambridge (MA): MIT Press.
Hill, Virginia & Pirvulescu, Mihaela (to appear) French object clitics, L1 and the left
peryphery, In Sandrine Ferré, Philippe Prévost, Laurie Tuller, & Rasha Zebib
(Eds.), Selected Proceedings of the Romance Turn IV Workshop on the
Acquisition of Romance Languages. Cambridge: Cambridge Scholars
Publishing
Hulk, Aafke & Muller, Natasha (2000). Bilingual first language acquisition at the
interface between syntax and pragmatics. Bilingualism: Language and
Cognition, 3(3), 227–244.
Jakubowicz, Celia, Müller, Natasha, Kang, Ok-Kyung, Riemer, Beate & Rigaut,
Catherine (1996). On the acquisition of the pronominal system in French and
German. In Andy Springfellow, Dalia Cahana-Amitay, Elizabeth Hughes &
Andrea Zukowski (Eds.), Proceedings of the 20th annual Boston University
Conference on Language Development (pp. 374–385). Somerville (MA):
Cascadilla Press.
Jakubowicz, Celia, Müller, Natasha, Riemer, Beate & Rigaut, Catherine (1997). The case
of subject and object omissions in French and German. In Elizabeth Hughes,
Mary Hughes & Annabel Greenhill (Eds.), Proceedings of the 21st annual
Boston University Conference on Language Development (pp. 331–342).
Somerville (MA): Cascadilla Press.
Lambrecht, Knut & Lemoine, Kevin (1996). Vers une grammaire des compléments zéro
en français parlé. In Jean Chuquet & Marc Frid (Eds.), Absence de marques et
représentation de l’absence 1 (pp. 279-309). Rennes: Presses universitaires de
Rennes.
Mavrogiorgios, Marios (2009). Proclisis and Enclisis in Greek. Unpublished doctoral
dissertation, University of Cambridge.
Müller, Natasha, Crysmann, Berthold & Kaiser, Georg A. (1996). Interactions between
the acquisition of French object drop and the development of the C-system.
Language Acquisition, 5, 35–63.
Pérez-Leroux, Ana T., Pirvulescu, Mihaela & Roberge, Yves (2008). Null objects in
child language: Syntax and the Lexicon. Lingua, 118(3), 370-398.
Pérez-Leroux, Ana T., Pirvulescu, Mihaela & Roberge, Yves (2011). Topicalization and
object drop in child language. First Language, 31 (2), 1-20.
Pirvulescu, Mihaela (2006). Theoretical implications of clitic omission in early French:
spontaneous vs. elicited production. Catalan Journal of Linguistics, 5, 221-236.
Mihaela Pirvulescu & Hill, Virginia (2011). Object Clitic Omission in French-Speaking
Children: Effects of the Elicitation Task. Language Acquisition, 19:1, 73-81.
Roberge, Yves (1990). The Syntactic Recoverability of Null Arguments. Montreal:
McGill-Queen’s University Press.
Salomo, Dorothé, Lieven, Elena, & Tomasello, Michael (2010). Young children’s
sensitivity to new and given information when answering predicate-focus
questions. Applied Psycholinguistics, 31, 101–115.
Schaeffer, Jeannette (1997). Direct Object Scrambling and Clitic Placemen in Dutch and
Italian Child Language. Unpublished doctoral dissertation, University of
California, Los Angeles.
Schaeffer, Jeannette (2000). The Acquisition of Direct Object Scrambling and Clitic
Placement. Amsterdam: John Benjamins.
Serratrice, Ludovica, Sorace, Antonella & Paoli, Sandra (2004). Crosslinguistic influence
at the syntax–pragmatics interface: subjects and objects in English–Italian
bilingual and monolingual acquisition. Bilingualism: Language and Cognition,
7, 183–205.
Sigurðsson, Halldór A. (2011). Conditions on argument drop. Linguistic Inquiry, 42(2),
267-304.
Sportiche, Dominique (1996). Clitic constructions. In Johan Rooryck & Laurie Zaring
(Eds.), Phrase Structure and the Lexicon (pp. 213-276). Dordrecht: Kluwer.
Sportiche, Dominique (1998). Partitions and Atoms of Clause Structure. London:
Routledge.
Wexler, Kenneth, Gavarró, Ana & Torrens, Vicenç (2004). Feature checking and object
clitic omission in child Catalan. In Reineke Bok-bennema, Bart Hollebrandse,
Brigitte Kampers-Mahne & Petra Sleeman (Eds.), Romance Languages and
Linguistic Theory 2002 (pp. 253–268). Amsterdam: John Benjamins.