SUMMARY

When children acquire a language, they acquire the grammar of that language—the phonological, morphological, syntactic, and semantic rules. They also acquire the pragmatic rules of the language as well as a lexicon. Children are not taught language. Rather, they extract the rules (and much of the lexicon) from the language(s) spoken around them. The ease and rapidity of children’s language acquisition and the uniformity of the stages of development for all children and all languages, despite the poverty of the stimulus they receive, suggest that the language faculty is innate and that the infant comes to the complex task already endowed with a Universal Grammar. UG is not a grammar like the grammar of English or Arabic, but represents the principles and parameters to which all human languages conform. Language acquisition is a creative process. Children create grammars based on the linguistic input and are guided in this process by UG. Language development proceeds in stages which are universal. During the first year of life children develop the sounds of their language. They begin by producing and perceiving many sounds that do not exist in their linguistic environment: the babbling stage. Gradually their productions and perceptions are fine-tuned to their surroundings. Children’s late babbling has all the phonological characteristics of the input language. Deaf children who are exposed at birth to sign languages also produce manual babbling, showing that babbling is a universal first stage in language acquisition that is dependent on the linguistic input received. At the end of the first year, children utter their first words. During the second year, they learn many more words and they develop much of the phonological system of the language. Children’s first utterances are one-word “sentences” (the holophrastic stage). Many experimental studies show that children are sensitive to various linguistic properties such as stress and phonotactic constraints, and to statistical regularities of the input that enable them to segment the fluent speech that they hear into words. One method of segmenting speech is prosodic bootstrapping. Other bootstrapping methods can help the child to learn verb meaning. based on word meaning (semantic bootstrapping). Distributional evidence such as word frames contributes both to syntactic and semantic knowledge. After a few months the child puts two or more words together. These early sentences are not random combinations of words—the words have definite patterns and express both syntactic and semantic relationships. During the telegraphic stage, the child produces longer sentences that often lack function or grammatical morphemes. The child’s early grammar still lacks many of the rules of the adult grammar, but is not qualitatively different from it. Children at this stage have correct word order and rules for agreement and case, which show their knowledge of structure.

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