[Interrogative] 어떻게 (how)
We use "어떻게" when we want to ask how an event happens.
"여기까지 어떻게 왔습니까?" is "How did you get here?", "버스로요." is "By bus."
[Interrogative] 왜 (why)
We use "왜" when asking about the reason or cause of an event.
"왜 학교에 늦었습니까?" is "Why did you late for school?"
[Interrogative] 언제 (when)
We use "언제" when we want to ask about time.
"쇼는 언제 시작합니까?" is "When does the show start?"
[Interrogative] 어디 (where)
We use "어디" when we want to ask about a place. "어디 + 를" can be shortned as "어딜".
"어디 가세요?" or "어딜 가?" is "Where are you going?"
[Interrogative] 누구 (who/whom)
We use "누구" when we want to ask about a person. "누구 + 가" is shortened as "누가", and "누구 + 를" can be shortened as "누굴" . We do not use "누구가".
"이 사람은 누구입니…
[Interrogative] 무엇 (what)
We use "무엇" when we ask about an thing/object. It can be shortend as "뭐".
"무엇이" is shortened to "뭐가", "무엇+을" is shortened to "뭘", "무엇이 문제입니까?" is "What is the …
[Numeral-determiner] 몇 (how many)
It comes before a counting unit and used in a question. "장" and "명" is counting units for paper and people, respectively. There are many counting units in Korean depending on the objects.
"CD가 …
[Comparison] ~중에서 제일/가장 + (부사) (most (adverb) among~)
we use "~중에서 제일/가장 + adverb" to say somebody/something is most adverb among others.
"K–pop 가수 중에서 누가 제일 좋아?" is "Who is your favorite K–pop singer?"
[Infinitive] ~지 말다 (do not)
The verb "말다" is not usually used in its basic form. Rather, it is more often used in the form of "맙시다" or "마세요" when advising somebody not to verb.
[Infinitive] ~ㄹ 수 있다/없다 (can do)
"~ㄹ 수 있다(없다)" simply means the subject has not the ability to do something. You can use "–ㄹ 수 없다" instead of "못~".
"나는 수영할 수 있다." is "I can swim.", "나는 …
[Infinitive] 못 + (동사), ~지 못하다 (be poor at (verb))
When somebody is poor at doing something, or somebody cannot do something very well because he/she lack the ability to do it. we use "못~", or "~지 못하다".
"그녀는 매운 음식을 못 먹…
[Infinitive] 잘 + (동사) (be good at (verb))
When somebody is good at doing something, or somebody does something well, we use "잘~".
"그녀는 젓가락짓을 아주 잘 한다." is "She can use chopsticks very well.", "그는 축구를 잘 …
[Infinitive] 못 + (동사), ~지 못하다, ~ㄹ 수 없다 (can not (verb))
When somebody cannot do something, usually not by his/her will, but because of another situation, we use "못~".
"He broke his leg. He cannot walk." is "그는 다리가 부러졌다.", "그는 못 …
[Infinitive] 안 + (부사), (부사) + 지 않다 (be not)
"안~" or "~지 않다" simply means that somebody/something is/be not adberb. We usually use "안~" in casual conversation and "~지 않다" in writing.
"He is not cute." is "그는 안 귀엽다." …