一、情态动词的基本用法(1)
[观察例句]
1．The police still have not found the lost child，but they are doing all they can.
2．Our daughter could walk when she was nine months old.
3．Accidents can happen on such rainy days.
4．We may go to the cinema tonight，but we are not sure yet.
5．That might be our taxi but I doubt it.
6．I could do it now，if you like.
7．Must I give up smoking?
8．Did she have to pay a fine?
