On the left periphery of the clause

Ever since the advent of generative grammar, much work in syntax has been devoted to the structure of the clausse and its two-part configuration: the core of the clause, on the one hand, and the left periphery, on the other.By left periphery, I mean any lexical material that appears to the left of the canonical subject position.In (1a), for example, we find a neutral word order (Subject-Auxiliary-Verb-Object), whereas in (1b), the interrogative equivalent of (1a), we see that the auxiliary 'has' appears to the left of the clause (Auxiliary-Subject-Verb-Object).(1) a. Claudia has watched a movie.b. Has Claudia watched a movie?Originally, the core clause was labelled S (for sentence) while the left periphery was labelled COMP (see Bresnan 1970).For theoretical reasons (the rise of X-bar theory, Chomsky 1970; Jackendoff 1977) as well as empirical reasons (two elements can appear to the left of the canonical subject, as shown by ( 2)), two positions were postulated for the left periphery: COMP and its specifier, as in (3), the idea being that the wh-phrase 'what' appears in the specifier position while the auxiliary is in COMP.(2) What has Claudia watched?(3) CP specifier C COMP Wh-phrases are not the only elements that can be fronted in English and other languages.Topics (4a) or focused elements (4b) are often fronted to the left of the canonical subject: