Topic

The topic is that part of an utterance about which something is said (the comment). Usually, the topic is given in the discourse, the comment is new information about it. The topic is thus the part of the proposition that is being talked about (predicated). Once stated, the topic is therefore "old news", i.e. the things already mentioned and understood.


 * "An entity E is the topic of a sentence, S, iff in using S the speaker intends to increase the addressee’s knowledge about, request information about, or otherwise get the addressee to act with respect to E." (Gundel 1988:210)

Examples
For example, the topic is italicized in the following sentences:

The dog bit the little girl. The little girl was bitten by the dog. It was the little girl that the dog bit. The little girl, the dog bit her.

Comments
One test for determining the topic of a sentence A is by formulating a question Q to which A might be the answer. The topic should then be the information common to both Q and A.

Q: What about Mary? A: John is taking care of her

In this context her ('Mary') is the topic of sentence A.

Synonym

 * theme (i.e. topic)

Subtypes

 * aboutness topic
 * sentence topic vs. discourse topic
 * stage topic

Examples
Many languages, like English, resort to different means in order to signal a new topic, such as:


 * Stating it explicitly as the subject (which tends to be considered more topic-like by the speakers).
 * Using passive voice to transform an object into a subject (for the above reason).
 * Emphasizing the topic using clefting.
 * Through periphrastic constructions like "As for...", "Speaking of...", etc.
 * Using left dislocation (called topic fronting or topicalization, i. e. moving the topic to the beginning of the sentence).

There are some other languages, like Japanese, that work directly on a topic-comment frame. A new topic is always introduced in a specific way, like with a topic marker (Japanese uses a postposition, wa). The topic can be the subject or the object of a verb, but it can also be an indirect object or even an oblique complement of any kind. It is always dislocated to the front of the sentence.

Signaling the topic as such serves the pragmatic function of avoiding repetition. In many languages, old topics are replaced with a pronoun. Pro-drop languages like Japanese tend simply to delete the old topic, which is then left implicit throughout the discourse until a new one appears.

Consider the following data from Japanese:

(i) a Taroo-wa kaeru-o koros-i-ta Taroo-TOP frog-OBJ killed 'Taroo killed the frog' b Kaeru-wa Taroo-ga koros-i-ta frog-TOP taroo-SUBJ killed 'The frog Taroo killed'

In (i)a the subject Taroo is marked for TOPIC by wa ; in (i)b Taroo is marked for SUBJECT by ga.

Link

 * Utrecht Lexicon of Linguistics