Topic-comment-distinction

Definition
Topic-comment-distinction is the division of a sentence into the thing that is talked about (the topic) and what is said about it (the comment). In simple sentences this distinction coincides with the distinction between subject and predicate, but the topic-comment-distinction can also be expressed by topicalization, left-dislocation and cleft-constructions, or by prosodic means. Some authors identify this distinction with the distinction between focus and presupposition or theme and rheme.

Links

 * Utrecht Lexicon of Linguistics