情态动词can的基本用法
情态动词can的基本用法：
情态动词can有一定的词义，但不能独立存在，它必须与动词原形一起构成谓语。情态动词can没有人称和数的变化。其具体用法如下：
1. 表示"能、会",指脑力或体力方面的"能力"。例如：
I can speak En glish. 我会讲英语。
Jim can swim but I can't. 吉姆会游泳，但我不会。
2. 表示"可能",常用于否定句或疑问句中，指某种可能性，此时can 't译为“不可能”。例如：
Han Mei ca n't be in the classroom. 韩梅不可能在教室里。
Can he come here today, please? 请问他今天能到这里来吗？
3. 表示"可以",常用于口语中，指许可或请求做某事，可以代替 may。例如:
Can I have a cup of tea, please? 请问我可以喝一杯茶吗？
You can go out. 你可以出去了。
补充：can的过去式could，意为“能、会”，表示过去的能力
女口： He could write poems when he was 10. 他十岁时就会写诗。
could在疑问句中，表示委婉的语气，此时could没有过去式的意思。
如:Could you do me a favour? 你能帮我个忙吗？一 Could I use your pen?我能用一下你的钢笔吗？一Yes, you can.可以。（注意回答）
情态动词can的基本句型:
1. 肯定句型为：主语+can+动词原形+其它。例如：
They can play basketball. 他们能打篮球。
She can dance.她会跳舞。
You can go to watch TV. 你可以去看电视了。
2. ........................... 否定句型为：主语+can not（can't/cannot）+ 动词原形+其它。表示"某人不能（不会。不可能）做其中can't是can not的缩略式，英国多写成cannot。例如：
You cann ot pass the ball like this. 你不能像这样传球。
I ca n't ride a motorbike. 我不会骑摩托车。
3. 疑问句句型分为：一般疑问句句型和特殊疑问句句型两种类型。
⑴一般疑问句句型为:Can+主语+动词原形+其它。表示"某人会（能。可以）做吗?",用于口语时，常表示请求或许可。其肯定答语用""Yes,主语+can."作答; 否定答语用"No,主语+can't."作答。注意答语中做主语的人称代词,应根据问句中的主语作相应的变化。其变化规则为：第一人称问，则第二人称答；第二人称问，则第一人称答;第三人称问，第三人称答。例如：
①-Can you sing an En glish song for us? 你可以为我们大家唱一首英语歌吗？
-Yes.行。（注意在Yes后面常省略lean）
②-Can I skate?我可以滑冰吗？
-Yes, you can.可以。
③-Can she climb hills? 她能爬山吗？
-No, she can't.不，她不能。
⑵特殊疑问句句型为：
a. Who+can+ 动词原形+其它。该句型中who相当于主语。例如：
-Who can sing in English in your class? 你们班上谁会用英语唱歌？
-Lily can.莉莉会。
b. 特殊疑问词（作定语）+名词+can+主语+动词原形+其它。该句型中的特殊疑问词常用 how many, how much 等。例如：
-How ma ny boats can you see in the river? 你能看见河中有多少只船吗-Only one boat. 仅有一只。
c. 特殊疑问词+can+主语+动词原形+其它。该句型中的特殊疑问词常用what, where, whe n 等一般用肯定陈述句作答。例如：
-What can you see in the picture? 你能在图画中看到什么？
-I can see some birds and two big trees in it. 我能看至 U—些鸟儿和两棵
大树。
考查can的用法:
a. 考查can表示能力的用法。
在这一用法中，can表示能力，意思是"能，会"，其否定式can't表示
不能"。在过去时中用could和could n't。例如：
1. --- Where's Mr. Lee? I have someth ing unu sual to tell him.
---You ________ find him.
A. may not
B. may not
C. can't
D. can't
2. --- Finish drawing a horse in ten minutes. OK?
---Sorry. It ______ in such a short time.
A. may do
B. can't be done
C. must do
D. n eed n't
be
done
3. I have my own room in my house, so I ______ do what I want in it.
A. must
B. have to
C. n eed to
D. can
4. _______ you mend my car? I ______ not start it.
A. Would; would
B. Must; must
C. Can; can
D. May;
may
5. _______ she ride whe n she was three years old?
A. Can
B. Could
C. Need
D. May
6. The boy ________ an swer this kind of hard questi ons one year ago.
A. can
B. may
C. could
b. 考查can表示推测的用法。
在这一用法中，can意为"可能"，表示客观可能性，常常用于疑问句和
否定句中。例如：
7. --- Who is the man over there? Is it Mr. Li?
---No, it _______ be him. Mr. Li is much taller.
A. must n't
B. may not
C. can't
D. n eed n't
8. --- Liste n! Some one is si nging in the n ext room. Who i t be? Is it Wei Fan g?
---No. It _______ be her. She is at school now.
A. will; may not
B. must; must n't
C. may; can't
D. may; won't
9. --- Is Mr. Hu in the reading room?
---No, he _________ be there. He has gone to Tianji n.
A. must n't
B. need n't
C. won't
D. can't
10. Class 3 won the football match! _____ it be true?
A. May
B. Must
C. Will
D. Can
c. 考查can / could 表示请求许可的用法
在这一用法中，can和could都表示现在，用could比用can语气更加委婉客气，常用Could I / you...?句式，表示"我/你能... 吗?"，若表示同意要用can ,不用could。例如：
11. --- Could I look at your pictures?
---Yes, of course you ______ .
A. could
B. can
C. will
D. might
12. _______ you pass me a pen? rd like to write dow n the
teleph one nu mber.
A. Need
B. Could
C. Must
D. Should
综合练习：
1. ---Can I go fishing with you, Dad?
---No, you ____ .You _______ stay at home and do your homework first.
A. won't; may
B. can't must
C. should n't; ought
D. n eed n't; should
2. ---Do you know whose dictionary it is?
---It _____ be Li Mei's. Her name isn ' t on it.
A. can't
B. must n ' t
C. should n't
D. need n't
3. ---I can't stop smok ing, doctor.
---For your health, I'm afraid you __ .
A. can
B. can't
C. must
D. must n't
4. ---Is Mr. Brow n driv ing here?
---rm not sure. He _____ c ome by trai n.
A. may
B. shall
C. need
D. must
5. —____ your friend play basketball?
—No, he _____ .
A. Cans; can ' t
B. Can; doesn ' t
C. Does can; doesn ' t can Can; can 't