주어진 문장의 밑줄 친 부분에 잘못이 있는 것은?

① there is nothing for it but to surrender.
② students should avail themselves to the books in the library.
③ he went on with his work.
④ she did nothing but cry all day long.

이거 답이랑 왜 맞는지 틀리는지 상세한 해설 부탁드려요 ^^
1번4번 어떤 구조인지 전혀 몰겠어요 해석도