* 가르치다: teach. 선생님은 30명 학급을 가르친다 (Our teacher teaches a class of 30). * 가르쳐 주다: teach, or tell/inform someone about something. - 나는 친구에게 어제 일에 대해 가르쳐 주었다 (I told my friend about what happened yesterday). Verb + 주다 (do for someone) generally does not change the meaning of the verb, but 가르치다 and 가르쳐 주다 is an exception. It changes the meaning too sometimes. * 살다: live. * 있다: 1. exist, be. 2. stay (in/at some place). 3. (as a helper verb) be in certain state/condition. * 계시다: honorific form of 있다, used for person older or at a higher position. * 살고 있다: is living/residing (#3 meaning of 있다). 그는 부산에 살고 있다: He ls residing in Busan. * 살고 계시다: honorific version of 살고 있다. - 친구는 외국에 이민가서 살고 있다: My friend is living in a foreign country as an immigrant. - 작은 아버지는 외국에 이민가서 살고 계시다: My uncle is living in a foreign country as an immigrant. - 걔들은 결혼해서 잘 살고 있다: They are doing fine living as a married couple. - 걔들은 결혼해서 잘 살고 있어요? (question form) - 걔들은 결혼해서 잘 살고 있지? "-지?" is a soft interrogative form, like confirming something one already knows.