情态动词
1．The police still haven’t found the lost child，but they’re doing all they ________.
A．can B．may
C．must D．should
2．I ________sooner but I didn’t know that they were waiting for me.
A．had come B．was coming
C．would come D．would have come
3．—Will you read me a poem，Mummy?
—OK. You ________ have one if you go to bed as soon as possible.
A．might B．must
C．could D．shall
4．—You didn’t wait for Elizabeth last night，did you?
—Yes，but we __________.She didn’t come at all.
