Noun, No-adjective
1. topic; subject
Wikipedia definition
2. Topic–commentIn linguistics, the topic (or theme) of a sentence is often defined as what is being talked about, and the comment (rheme or focus) is what is being said about the topic. This division of the information structure of the sentence is generally agreed upon, but further than this the definition of what constitutes a "topic" is controversial and depends on which particular grammatical theory is being employed.
Read “Topic–comment” on English Wikipedia
Read “話題” on Japanese Wikipedia
Read “Topic–comment” on DBpedia


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