精进英语__情态动词 （1a）

情态动词的学习，记大致可从两个方向把握。一种是要抓住3点的：①表能力；②表允许；③表推测。如can/may(见下表)；另一种是要抓住2点的：①表责任义务；②表推测。如should/must；在此基础上，再根据需要去拓展其他的使用内容就比较容易了。金桥翻译h7t0~$F6qS;^c

1.       can，could 的用法

导读：关于能力

一般素质能力：某人天生就力气大，某人是数学教授等，这种能力不会今天有，明天无地随意改变；

特殊场合能力：在某个特定时间（如某天）做某个具体事件的能力

　　1.1表能力，有“能”、“会”、“能够”的意思金桥翻译w6_;b3?+Z1J1|[;{oG
　　例如：Can you drive a car?你会开车吗？金桥翻译 HVW#R,c|Y
　　-----Yes, I can.我会。金桥翻译9X(|Ie.M
　　-----No, I can't.我不会。

[精进]用一般现在时态，can可以不用考虑其一般能力与特殊场合的能力问题，也就是它此时等于is/are able to

I'm able to go to the fair. / I can go to the fair.
5EZ8y3}!P \)N8Q0I'm able to count to ten. / I can count to ten.
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Y0He can pass the English exam.金桥翻译ef+p"D$pO9}5M iOu
He is able to pass the English exam.
\z'cg-k3a Ewa(G O0注意时态：can没有将来及完成时态，故只有借用be able to金桥翻译(v2mS J'{I(UXZ

He will be able to pass the English exam.
4G)qOgi7^p&l_Tv0He will be able to…
'ql9z:UI+X%E8s0He has been able to…金桥翻译]B)Tg!d*E Te-m U T

[例题]Mild forms of exercise can ____ some of the loss of flexibility that accompanies aging.　［A］金桥翻译J#E*wV$NQ'_#iZ:r k5z

［A］stop　　　　［B］to stop金桥翻译kn4x;cy
［C］stopping　　［D］be stopped金桥翻译(e,V k#e4[.zt

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　　1.2表允许，在口语中代替may，有“可以”的意思金桥翻译:ti f z`Q
　　例如：Can I use your bike?　我可以用你的自行车吗？金桥翻译 rHgY+u }

[案例]

--Would you like to go swimming with me this afternoon?金桥翻译0gn9U;]0rS@S

-- I'd love to. But I'm afraid I ____. I have too much work to do.(2003)

A. can't            B. mustn't 金桥翻译G2Y_V i"q;g|'`

C. needn't         D. may not

解析：选A.这里的can't似难归类？它实际表示一种opportunity.是can在上述表格用法之外的一种分类法。金桥翻译 E,sR y#E]n-|

1.3表推测，常用于否定句和疑问句

导读：英语中的推测有理论上的推测与事实上的推测之说法。汉语中也有这情况，只是我们平时不太注意而已：

这条路是可以堵上的；

这条路可能被堵上了。

上面一句的意思是，你可以用种种手段，理论上总可以有办法把那条路堵起来。我们发现这样的话总是很难驳倒，也就是，它是个大道理，是种判断。

下面那句话，说得是，可能路面上有交通堵塞之类的事情，或者有很多人往回走之类的事情，是个现实的情况。金桥翻译qif,z:yJG!J

用英语，两句话分别是金桥翻译5T@:x6YpX

The road can be blocked.

The road may be blocked.

3oz#G9O\q.i7O0　　CAN的推测用法：金桥翻译0A}+V [0g!cqVYQ

例如：Can it be true?　那会是真的吗？
d(E3s5\+b$^(Z0　　Today is Sunday. He can't be at school.　今天是星期天。他不可能在学校里。金桥翻译ICAj!VsI4H0FO

[精进1] can用于肯定句含义稍深些

Can不能用于肯定句对具体事实进行推测：金桥翻译)t o?q%G w:s A

例句§01  He can be a student. (X, 如果用来表示推测；用来表示潜能是另外一回事)

<学生就是学生，是个具体的事实(can应改为may/might/could)。你不能说“他在理论上可能是个人”，要使这句话成立，语境很难找出.说“他在理论上可能是个学生”与这句汉语类似，如果说他有那种潜在的能力这句话是对的>
(y`/RW r*W*V0例句§01 中的can可用could来处理（当然也可用may/ might），即：在现在时中，可用may/might/could表示对具体事实的推测:金桥翻译^0|v#tB;z^^q`

The news may/might come as a shock to many of the people present.

---- Why isn’t Tim here yet？金桥翻译8Y&yi3}9o

---- Itmay/might/couldbe because his mother is ill again.金桥翻译%WEIxb7g"Mo[-a

[精进2] can用于肯定句表推测是指理论上的推测，或简单地说是“科学判断，大道理”金桥翻译:n-TP~aCZ[

The temperature can sometimes reach35℃in July.

Too much love can sometimes be bad.

It may/ might/ could rain later. (这里不能用can)

例题Sometimes he is very friendly, but at other times he ____ behave coldly.
U/E,m:EU2\H0A. can               B. must金桥翻译
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C. will               D. shall.

[解]选A；C表推测，含义几乎等于“一定”"Will" is a prediction (it will happen for sure) whereas "can" points out a possibility (it may happen or it may not).金桥翻译1pR2KhI6Q UEc.c

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[精进3]However, we commonly use can or could, even when we are talking about specific occasions with verbs of senses, feel, hear, see, smell, taste and with verbs of ‘thinking’, e.g. believe, decide, remember, understand:金桥翻译,{;Ay J0DE)X

She could feel the spray on her face as the boat raced through the water.金桥翻译xD8YV/Rp

I can’t decide where to go for my holidays.金桥翻译B*M~m*m^#txm

[精进4]However, when we make decision now about something in the future, we use can.金桥翻译a$wBb
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You can go home when you’ve finished writing your composition.金桥翻译io u-QmJp

Perhaps we can meet next week.

(摘自English in use)

1.4过去式could表示的语气更加委婉、客气
,i m Nr4^)?0　　例如：Could I come to see you tomorrow?　明天我可以来见你吗？金桥翻译2pcp\6s*lwd5M

⊙本小节需掌握的其他知识点
L"OW{ V.~RR5a)|E0　　①can 和 be able to 的比较金桥翻译`q}j9yCB

can与be able to都可以表示能力，但两者在用法上有点差异：金桥翻译,pk0I-UY Tr}

can用于现在时，表示一般能力，也可表示某次的能力；金桥翻译u x(e5`h*B(~ N
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could用于过去时，表示素质能力或说一般能力，不能用于某次的能力。此时was/were able to表示某次能力，指成功地做成了某事。

时态变化有will be able to do; have been able to do等

例如：金桥翻译B,ZS j1i

He can pass the examination.金桥翻译X+G[C \%q:J,L

He was able to pass the examination.金桥翻译;sR k7w|
　My grandma is over seventy, but she can still read without glasses.
3r]3OdL0  He is able to give up his bad habits.

I haven't been able to get in touch with her.　我一直没能和她联系上。金桥翻译O9x s Z.Z{:{^

[例]The fire spread through the hotel very quickly but everyone ____ get out.   选D金桥翻译v#|2R}?*u

A. had to B. would C. could D. was able to
h0hk&de2p5`Y0【解】注意是could，它与was able to的意义与用法不同。

[例]—Didn’t they come to the party last week?

—Yes. They didn’t want to come with us at first, but then we ____ persuade them.金桥翻译t,vP2i6Q5i7wW,|D

A. would B. could  C. were able to D. had to金桥翻译a'^A#C~ K8D_W.KL

【解】考察could与was able to表示"能力"的用法。表示某一次的能力，常用be able to，但在否定句中可用couldn’t与wasn’t /weren’t able to是不作区别的。答案C。金桥翻译 l8TsDlds

[例]They didn’t agree with me at first, but in the end I ___ persuade them.金桥翻译4v z-j!C#^6}O

A. might as well   B. would      <D>金桥翻译 d%C#Jm7P!y#Du4?

C. could          D. was able to     

[例]The fire spread through the house very quickly but everyone ____ get out.金桥翻译 e5M5n'mk0_wv/WR
A. could  B. was able to              <B>

[例]I don't think physics is so hard, and I _____ study it.
#YSi Yr6c0A. am able to金桥翻译8QRt:e6VK,a0CM
B. can金桥翻译UO|KjFt;X-X
EA
C. could金桥翻译#g&V7[/].PK9ZE

AE：All three choices would mean the same to me in this lone sentence.

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[案例1] (could的大致用法)金桥翻译4CVf#WbA

Maybe youcouldmeet me at smith's restaurant like last time

AE: "Could" is just another way of saying "would be able to".Maybe you would be able to meet me at Smith's Restaurant like last time."Could" indicates that the action will take place in the future and is used in this case to express a wish (or want).

BE: "Could" is used to express possibility or past ability as well as to make suggestions and requests.
0d#y#x)e a1})A&C,t0"He could be the one who shouted" (possibility)金桥翻译+D(lRR1sm4X6`
"You could spend your holiday in Ireland" (suggestion)金桥翻译-b#K\7hri Xs
"I could run fast when I was young" (past ability)金桥翻译E9m(uq['t,`^j
"Could I have a cup of tea?" (polite request).
X)]Ak0jGa0"Can" is used to express ability or opportunity, to request or offer permission, and to show possibility or impossibility.金桥翻译2G9Tc O;Yq;o(Bp
"I can speak English" (ability)金桥翻译)fD;i6Q+R0y i'o
"I can show you now" (opportunity)金桥翻译^ui:_"P+jVJ
"I can start the engine now" (permission)
rq|H ]I/?0"Can I have a beer" (request)
M*vP}[3e.{0"Anyone (Not everyone) can become President" (possibility or impossibility)

[案例2] could表一般能力的用法情况金桥翻译b"~*g~K!iTn#F

Q：下面的was able to能否换成could?金桥翻译4JJv0U ^Ak U%Upv3J

1 He worked so hard that he was able to pass the exam.
]Av"_Ruq02 The weather was so nice that he was able to reach the top.金桥翻译2HvEW&[

答：不能。pass the exam / reach the top.都指具体的某次行为，而could指一般的素质

Q："I could pass my driving test yesterday."

Dimcl：Yes, indeed, it's very wrong! "Could" and "would" arepossibility. You "could" pass your driving test tomorrow but not yesterday because that's not possible. You may have been able to pass your driving test yesterday and you may be able to pass it tomorrow.

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(待续1b)