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THEORETICAL BACKGROUND AND FRAMEWORK

2.2 GENERAL BACKGROUND AND CONCEPTS

There are some basic questions which studies on first language acquisition generally aim to answer: How do children systematically acquire language? Is there a strict developmental order to language? What factors affect linguistic development? Various methods have been employed in studies aimed to answer these questions; despite the differences in methodologies, all studies converge on the fact that any human child can acquire the language of their linguistic community effortlessly, without explicit teaching, on the basis of positive evidence, under varying circumstances, and in a limited amount of time. In addition, despite great differences in input and in conditions of acquisition, this process is achieved in remarkably uniform ways cross-linguistically. For example, at about 6 - 8 months all children start to babble; at about 10 - 12 months they speak their first words and between 20 and 24 months they begin to put words together (Guasti, 2002). Also the structures that children form are similar across languages, whether they are target-consistent or not: for example research

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shows that children in the initial stages of language acquisition omit sentential subjects, regardless if these are features of the target language. Additionally, it is observed that by the time children begin to utter word combinations equivalent to full sentences, they have already figured out the rules governing word order and the position of verbs in the sentence. Thus the production of a child acquiring English will manifest Verb-Object (VO) order while that of a child learning Japanese will manifest Object-Verb (OV) order. French learners position the inflected verb to the left of the negative particle pas while English learners position the negative particle before the verb, as in the corresponding target language (Pierce 1992).

The vast majority of these results in acquisition studies, as reported above, originate from research on the acquisition of major European languages. It is quite recent that research on non-European languages (such as Japanese, Korean, Hebrew, and others) has become significant. What is still lacking however, as alluded to in the Introduction, is research on the acquisition of creole languages. It is important to include different types and families of languages such as creoles in order to strengthen theory-guided research in acquisition.

Despite the languages being studied or the methodology and framework adopted, there are some basic concepts which most syntactic theories of first language acquisition have adopted.

Some of these basic concepts underlying research in the domain of first language development will be now discussed.

9 2.2.1 Basic Concepts and Ideas1

Language entails a psychological system realized in our mind/brain called a grammar. Our linguistic knowledge allows us to produce an infinite set of utterances from a finite set of lexical items, and also to understand sentences that we have never heard before. Additionally, it gives us a tool to assess the acceptability of such utterances in accordance with the rules of our language and the associated interpretation or meaning of the utterance. In short, grammar is a system which ascribes certain structural representations to sentences and sanctions certain interpretations while forbidding others. It does this by means of constraints that establish whether certain constructions are possible or not possible in a language. Constraints are linguistic principles that prohibit certain arrangements. Sentences that are considered well-formed or acceptable in a particular language must conform to the linguistic constraints governing the language. But how do children gain this grammatical knowledge?

Different hypotheses have been advanced, one of which holds that children learn language through imitation (see Fraser et.al, 1963). The general idea here is that children imitate what adults say by trying to repeat what they hear. However several facts showing that there is no necessary similarity between the linguistic input that children receive and their subsequent linguistic output argues against this hypothesis. For example children produce novel utterances that they have never heard because the adult speakers in their environment do not produce them. So an English learner would over regularize irregular past tense verbs, produce target-inconsistent negation, utter ill-formed questions, etc. Moreover, children hear a finite number of sentences, however they are able to produce and understand many sentences, including those that they have never heard before and therefore cannot be imitating. Another

1 Ideas and discussions from this section are mainly from (Guasti, 2002).

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idea is language learning through reinforcement. According to this view, children learn language because they are positively reinforced when they produce correct utterances and negatively reinforced when they make errors. This is in-line with one of the earliest scientific explanations of language acquisition, known as behaviourism (Skinner 1948). The main idea here is that children learn by echoing the behaviour of others, and when done correctly, is positively reinforced. This hypothesis however, like the acquisition through imitation hypothesis, cannot explain how humans acquire language and cannot characterize human linguistic competence. First, it cannot explain how children acquire competence over an indefinite number of sentences for which no reinforcement was provided. Second, in parent child discourse, parents do not normally check for grammatical correctness, and if they should do so, such corrections go unnoticed. Reinforcement therefore does not explain human linguistic attainment.

The answer that Chomsky (1959 and much subsequent work) gave is that this grammatical knowledge is based on an inborn predisposition. Arguments from the poverty of the stimulus, that all speakers of a language know only a fairly abstract property and that this property cannot be induced from the evidence available to children (positive evidence), point to the requirement of an innate language mechanism. The hypothesis that the language capacity is inborn and richly structured explains why language acquisition is possible, despite all limitations and varying circumstances in which language learning takes place. It also explains the parallels in the time course and content of language acquisition. Though languages are similar, in accordance with this innate mechanism, there are very obvious variations. These variations are however not unlimited, but are restricted by Universal Grammar (UG). UG is the name given to the set of constraints with which all humans are endowed at birth and that are responsible for the course of language acquisition.

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Based on this background we will now examine the theoretical framework that guides the present research.