情态动词基本用法专题总结大全讲解与练习
情态动词 用法 例句 注意事项
can
could 1表许可(和may可互换)、能力
2表怀疑、猜测、可能性（用于否定和疑问句中）
3 could可表比can更委婉的语气及用于虚拟语气。 1You can/may sit here./He can swim.
2 He can’t be sixty.
3 Could you come again tomorrow?
can和be able to都可表能力，但be able to可表达“某事终于成功”，有更多的时态。
may
might 1表可以（问句中表请求，might更婉转）
2表可能，或许（might语气更加不肯定）

3表祝愿（用于倒装句中）

语法易错题
英语单词记忆
英语语法练习题
 

1 May/Might I use your bike?

2 He may/might be at home.

3 May you succeed! 

1回答May…do…?的否定用 mustn’t/can’t

2回答May/Might…
do…?的否定用 can’t/might not

must   1表必须，应该（表主观要求）
2表推测（用于肯定句），译为“准是，一定”   1 You must study hard.
2 She must be tired.   否定式mustn’t表不准，禁止；否定回答用needn’t/don’t/doesn’t have to(不必)
have to   只好，不得不（客观的必须，有时态人称变化）   Without help, I had to do it myself.   must表主观意识。have to有多种时态。
ought to   应当（表示义务责任，口语中多用should   You ought to obey laws.   否定用oughtn’t 疑问句用Ought…to do…?

shall   1用于一三人称的疑问句，表征询意见
2用于二三人称, 表示许诺、命令、警告等   1 Shall we go now?
2 The sign there reads, “No person shall smoke here.”  
should   1表建议或劝告，译为“应该”
2本该（含有责备意味）   1 You should learn from each other.
2 You should have given him help.  

will
would   1表意志或决心
2疑问句中用于第二人称表请求，would比较委婉   1 He promised he would never smoke again.
2 Will/Would you like some tea?   would表示过去的习惯或喜好,不涉及现在; used to表示过去常常做现在已经不再有的习惯.

dare   敢（常用于否定句、疑问句和条件从句中）   He dare not/daren’t sleep alone.
Dare you touch it?   过去式dared；可作实义动词
need   需要,必须（常用于否定句和疑问句中）   You needn’t do the work now.   Need…do…?的肯定回答：Yes,…must. 可作实义动词
used to   过去常常（现在已不再）   He used to play football.   否定式usedn’t/usen’t to do/didn’t use to do; 疑问Used…to…do…?Did…use to do…?

填入适当的形容词、副词或用所给词的正确形式填空
1.   The number of the trees that the villagers planted last year reached as __________ as 6,000,000.
2.   There was so _________ smoke that they couldn’t see across the hallway.
3.   My little brother is not old ___________ to go to school.
4.   In that case, there is nothing you can do __________ than wait.
5.   I must be getting fat－I can ____________ do my trousers up.
6.   They are __________ little insects that we can not easily see them with our eyes.
7.   There was __________ little food left then that we had to turn to the local people for help.
8.   Mary kept weighing herself to see how much ___________ she was getting.
9.   I haven’t seen the movie and my brother hasn’t _____________.
10.   He is always telling lies, so I will ________ believe him.

答案： 1. many   2. much   3. enough     4. other  5. hardly   6. such   7. so   8. heavier  
9. either   10. never