The purpose of this study is to investigate the early wh-movement acquisition of English native speakers from the perspective of Minimalist Program. Guasti and Rizzi(1996) propose the null auxiliary hypothesis that the structure of the questions where the verb is inflected with -ing includes a null auxiliary, the counterpart of the lexical be. They draw a parallel between the null auxiliary and the early null subject. Rizzi(1997) proposes that the CP system, like the IP system, is layered. ForceP is the highest project which determines the clausal type and FocusP's specifier is the landing site for wh-operators and whose head hosts inverted auxiliaries. Guasti and Rizzi(1996) argue that children's auxless questions are structures truncated below ForceP. Thus, the null auxiliary, like other early phenomena, finds its source in the mechanism of clausal truncation. The phenomena of early language acquisition reflects the process of acquiring functional categories as children grow.

The purpose of this paper is to investigate agreement-feature checking and English root infinitives in child language from the perspective of Minimalist Program. To explain this apparent derivation from the target adult gram- mar, researchers have elaborated two main models. One is the Tense Omission Model and the other is the Truncation Model. Wexler (1994) proposes in the former that an optional infinitive clause arises when the child leaves the tense feature underspecified in a given clausal represen- tation. Rizzi (1993/1994) proposes in the latter that the Root Infinitive reduces structures that result from the option of truncating structures at different levels of the clausal architecture. A further expectation would be that nominative Case is not assigned properly if AgrP is not yet projected. In the Minimalist Program, T inherits Agree-feature from C, but root infinitive clauses don`t have TP. Therefore, in children`s speech, functional projections are truncated below CP. The phenomena of early language acquisition reflects the process of acquiring functional categories as children grow.