Implicature for Plurals in Child Grammar
Terue Nakato-Miyashita and Tom Roper
Kitasato University and University of Massachusetts, AmherstChildren seem, surprisingly, to misunderstand plurals: they answer “yes” to the question like(1) (Sauerland et al. (2005)).
(1) Does a dog have tails?
Why do children give such a non-adultlike answer and how do they obtain the adultrestriction? One possibility is that children cannot compute an implicature associated with theinterpretation of bare plurals (cf. Spector (2007)). Bare plurals sometimes allow singularreference as in (2).
(2) Does your office have windows? -- Yes, one.
(Sauerland et al. (2005))
Their interpretive possibility is contextually determined and rejection of that possibility
depends upon an implicature that there is a better way to say it: a dog has a tail. Theinterpretation of definite plurals, on the other hand, is semantically determined given theassumption that the definite determiner selects the maximal element from the set denoted bya plural noun. Little is known about how children acquire such an intricate distinction
between bare and definite plurals. The aim of our presentation is to give predictions made bysyntactic and semantic proposals on adult grammar, together with an acquisition principle,and to provide acquisitional evidence for them.
Various proposals have been made with respect to the semantics and syntax of nominal
projections. Chierchia (1998) argues that the semantics associated with root nouns isparametrized and that a mass/kind semantics is given as a default value. The majority ofcurrent syntactic literature assumes that NP has extended functional projections such as DPand NumP (Longobardi (2001), Schmitt and Munn (2002), Munn and Schmitt (2005),
Watanabe (2006, 2009) among others). Another shared assumption is that a projection
associated with number is included in the extended projections above NP, such as NumP orφP (Sauerland (2003) among others). In order to give an appropriate interpretation tonominals, the semantics of number morphology and determiners, and implicature have to becomputed at the projections above NP.
Under these assumptions, it is the full-specification of the semantic and syntactic featuresat the functional projections that children must possess in order to determine exactly whereplural interpretation occurs. Plural interpretation would occur where Agreement occurs, DP.
Under the structure [D [NP and NP]], the conjoined NPs only become a plural at the DP
level: “the man and woman are here”. Then, it is natural that DP should be the level forimplicatures. Economy of representation (Pérez-Leroux and Roeper (1999)) suggests thatchildren should start with a minimal representation (NP not DP). If this is true, children go
through a stage only with NP, not DP (or a stage without full feature-specification offunctional projections), where nominals are uniformly given a mass/kind semantics. This
makes early English like Japanese where no number is represented on N. English children
could pass through a Japanese stage, but not the reverse. Therefore we predict:(3) Children will not reject a plural for a singular reference until (a) DP is represented withfully specified features and (b) implicatures are computed.
Children use the for a unique reference by three years old. However the with a singular noun
still does not guarantee DP. As de Villiers and Roeper (1995) observes, there is no DP barrier
initially and children seem to generate the as Spec-NP. Our earlier work (Nakato-Miyashita(2011)) has shown that 3-to-6-year olds fail to grasp number-morphology if number ismarked only on nominals. Also, implicatures have been argued to occur in the 5-to-7-year
range (see Huang and Snedeker (2009)). Then, we predict late recognition of the impact ofdeterminers on plural interpretation and further delay of the acquisition of the interpretation

of bare plurals. We also predict that children have further difficulty rejecting plurals for a
singular reference when there is a conflict between context and syntax with conjoined
nominals. Even adults easily say “yes” to a question with two conjoined nominals in thesituation where context provides a singular and a plural, for example, one pepper and twoonions.
In order to see if these predictions are correct, we conducted two experiments. In the firstexperiment, 50 6-to-8 year old children were given a picture and a question with an indefinite
singular, a bare plural, or a definite plural ((4)).
(4) Picture 1: A boy is looking at two books.
Instruction: This is Harry. Harry is looking at books that he likes.
Picture 2: The boy is holding one of the two books.
Test Sentence: Did Harry take a book/books/the books?
Our results show that even when the is present, only the 7- and 8-year-olds reject the test
sentences and that children are likely to start to make a distinction between bare and definite
plurals at around the age of eight.
Based on their response pattern in the first experiment, we asked 31 6-to-8-year-old
children to participate in the second experiment. They were divided into two groups: those
who tended to accept singular reference of plurals and those who could deny it. They weregiven a series of pictures and a question with coordinated plurals with a definite determineror coordinated bare plurals ((5)). Only in the former case, it is clear that a single DP
dominates two plural NPs.
(5) Pictures: Two children are talking about what they like (for example peppers andonions)  A mother bought one pepper and two onions.
Test Sentence: ‘Oh good. You bought the peppers and onions / peppers andonions.’ ‘Is that right?’
Our results show that it is hard for the children to reject a singular reference even if they
make a singular-plural distinction in the first experiment. The results also show that children
seem to start to make a distinction between definite and bare plurals at around the age ofeight.
This provides strong evidence that children do not compute implicatures when DP is not
fully represented. Our evidence also provides unique support for the idea that implicaturecomputation is directly linked not only to higher syntactic categories, but to categories whichvary parametrically cross-linguistically. This in turn provides evidence for the claim that thesyntax-semantics-pragmatics interface is UG-determined and not a result of purely cognitive
factors.
Selected References
Chierchia, G. (1998) “Reference to Kinds across Languages,” Natural Language Semantics 6,339-405.
Huang, Y. and J. Snedeker (2009) “Semantic Meaning and Pragmatic Interpretation in 5Year-Olds: Evidence from Real-Time Spoken Language Comprehension,” Developmental
Psychology 45, 1723-1739.
Munn, A. and C. Schmitt (2005) “Number and Indefinites,” Lingua 115, 821-855.
Sauerland U., J. Andersen, and K. Yatsushiro (2005) “The Plural is Semantically Unmarked,”in S. Kepser and M. Reis (eds.), Linguistic Evidence, Mouton de Gruyter, Berlin.
Spector, B. (2007) “Aspects of the Pragmatics of Plural Morphology: On Higher-Order
Implicatures,” Presupposition and Implicature in Compositional Semantics, ed. by U.
Sauerland and P. Stateva, 243-281, Palgrave MacMillan, Hampshire/New York.