内容正文:
情态动词不能单独作谓语,它必须和动词
原形连用一起构成谓语。
一、情态动词的情态意义表示法
考点一:can可表示现在或将来的能力,
意为“能;会”。can还可表示请求、允
许,意为“可以”。如:
Gabriella can speak French fluently.
Can you help me lift this box?
考点二:could可表示过去的能力;当
could表示允许时,语气比can更加委婉
和客气。如:
Could I have a drink of water, please?
考点三:may表示请求、允许,意为“可
以”。如:
May I come in and wait?
Thank you. You may go now.
考点四:might表示允许时,语气比may更
加委婉和客气。如:
Might I borrow your pen?
考点五:must表示义务、命令或必要,意
为“必须”,强调主观看法;表示“不必”,用
needn’t。mustn’t表示“不允许;禁止”之
意。如:
All passengers must wear seat belts.
You mustn’t talk to your mother like that.
考点六:have to意为“不得不”,强调客观
需要。如:
It is getting late. I have to go.
考点七:should意为“应该”,既可以表示义
务或责任,还可以表示劝告或建议。其否定
式为shouldn’t,意为“不应该”。如:
You should read his new book. It’s really
interesting.
Children shouldn’t be allowed to play in the
street.
考点八:had better do sth.意为“最好做某
事”,其否定式在better后加not。如:
You’d better (not) see the film yourself.
考点九:need表示“需要”,作情态动词时,
通常用于否定句或疑问句中。
1. — Yuan Longping, a famous Chinese
scientist, is now doing research on