1.Both of my brothers have already left university.（改为否定句）

1.Both of my brothers have already left university.（改为否定句）
__________of my brothers has left university_________.
2.Why don't you go to the school livrary with me?(保持原句意思)
_______ _______go to the school library with me?
_______ _______going to the school library with me?
3.Sam was very excited.He couldn't fall asleep.（保持原句意思）
Sam was _____ excited _________ he couldn't fall asleep.
Sam was __________ excited ___________fall asleep.
(twenty minutes' walk)用什么提问?