This sentence ending for questions, -(으)ㄴ가(요)? (–(eu)nga(yo)?) has the same purpose as the ending -나(요)? (-na(yo)?), but we use this one with the verb 이다 (ida – “to be”), and descriptive verbs, which are like adjectives but used like verbs in the Korean language.
Like -나(요), the ending -(으)ㄴ가(요) is also a sentence ending that Korean people use to avoid asking a question too directly. This ending also has the nuance of asking oneself at the same time as asking the other person, and it is similar to saying “I wonder…” in English. By using -나(요) or -(ㅇ)ㄴ가(요), people hope to be less direct and accusing when asking a question, because one gets the feeling that the asking nuance is weakened by being divided into two directions – half toward the other person and half toward oneself.
We use -(으)ㄴ가(요)? with the verb 이다 and descriptive verbs, whereas we use -나(요)? with action verbs. But in many cases, Korean people often mix up and use -나(요)? for descriptive verbs as well.
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