"Have you worked in Korea?"

Translation: 한국에서 일한 적이 있습니까?

[Kathinskowitz]

Where does the "적이" come from?

[wintertriangles]

한 적이 있다/없다 is a grammar form for expressing if one has ever done something before.

오페라를 본 적이 없어? - You've never seen an opera?

[Yoxdavox]

알겠습니다. 감사합니다.

[oee16]

Would be nice if DLG would add some reference note to the translation above. e.g.

<h1>Grammatical Structure</h1>

[V] + (으)ㄴ 적이 있다/없다
[Have ever (V) before / Have never (V) before]