Topic-marking particle (Korean)

In Korean, the topic-marking particle -은/-는 is used to mark the topic of a sentence. While the topic is almost always the grammatical subject, it's primarily a semantic concept. Much like the subject-marking particle, but with much deeper nuance.

In many cases, new topics are introduced with -은/-는, and thenceforth referred to with the subject-marking particle.

One can think about -는 as "shifting the conversational spotlight."

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