shall开头的句子要怎么回答

　　Mmm, I'm not so sure that's a good idea.

　　嗯，我不知道这想法行不行。

　　LL: Are you sure this is a good idea?

　　（严肃地）当然是个好主意喽！怎么会不是好主意呢？

　　I'm not sure that's a good idea.

　　我不能确信那是一个好主意。

　　Are you sure it's a good idea taking this back to yours?

　　你确定放在你那是个好主意吗？

　　If you're entertaining foreigners, be sure you have a good idea of their business practices!

　　如果你打算招待外国客户，一定要掌握他们的商业习惯。