(一)用情态动词表达事实的推测。can,could,might,may,must可以用来表达对事实的推测。根据说话人对事实的把握性大小,must表示"肯定…",may / might / can / could表示"可能……", must只用于肯定句中,may / might的否定式may not / might not表示 "可能不……", 而can / could可以用于疑问句,表示"可能,可能……吗?",其否定式can’t / couldn’t 表示"不可能"。用情态动词可以对现在或过去的事实进行推测。对不同的时间内容推测有不同的结构。
主要结构:…must / may / might +动词原形
1. You must be Jeanne. I’m Mathilde Loisel. We used to know each other very well.
2. They must be in bed already at this time of the night.
3. The teacher must be joking.
4. Freda isn’t in class. She must be sick.
5. There must be something wrong.
6. She might be very clever, but she hasn’t got much common sense.