1 . 选词填空

can, could, may, might, must（包含其否定形式）

1. Helen ________ go on a trip with us, but she isn’t quite sure.
2. My sister met him at the theatre last night, so he ________ have attended your lecture.
3. —I am sure I saw Brian in the park this morning.
—You ________ be imagining things. He left for America last night.
4. —Is John coming by bus?
—Not sure. He should, but he ________. He likes riding his bike.
5. —Isn’t that your teacher over there?
—No, it ________ be him. I'm sure he doesn’t wear glasses.
6. I saw him just now, so he ________ have gone abroad.
7. We ________ have faced the difficulty together, but why didn’t you tell me?
8. —What has happened to George? He hasn’t turned up so far.
—I don’t know. He ________ have got lost in the woods.
9. —She looks very happy. She ________ have passed the exam.
—I guess so. It’s not difficult after all.
10. For example, you ________ want to be a pilot but ________ become one because your eyesight is not good enough.