Word order | Generative syntax
Topicalization
Topicalization is a mechanism of syntax that establishes an expression as the sentence or clause topic by having it appear at the front of the sentence or clause (as opposed to in a canonical position further to the right). This involves a phrasal movement of determiners, prepositions, and verbs to sentence-initial position. Topicalization often results in a discontinuity and is thus one of a number of established discontinuity types, the other three being wh-fronting, scrambling, and extraposition. Topicalization is also used as a constituency test; an expression that can be topicalized is deemed a constituent. The topicalization of arguments in English is rare, whereas circumstantial adjuncts are often topicalized. Most languages allow topicalization, and in some languages, topicalization occurs much more frequently and/or in a much less marked manner than in English. Topicalization in English has also received attention in the pragmatics literature. (Wikipedia).
