Word때ttaeMeaningwhenPart of speechpostpositionPronunciationCourseHardcore KoreanLessonLesson 16Usages of ttae초를 켤 때 조심하세요.choreul kyeol ttae josimhaseyo.Be careful when lighting the candles.비행기를 탈 때 여권을 보여 주세요.bihaenggireul tal ttae yeogwoneul boyeo juseyo.