高中外研版 (2019)Unit 1 Food for thought学案

这是一份高中外研版 (2019)Unit 1 Food for thought学案，共3页。学案主要包含了情态动词的特征，情态动词的基本用法等内容，欢迎下载使用。


一、情态动词的特征
1．情态动词表示说话人对某一动作或状态的态度，有一定的词义，但不能单独作谓语，必须和动词原形，即不带t的不定式连用，才能构成谓语。
2．情态动词没有人称和数的变化(have t例外，主语是第三人称单数时，要用has t)。
二、情态动词的基本用法
1．be able t/can/culd
[观察例句]
①This time I failed，but I'll be able t pass the exam next time.
②Mary can speak three freign languages.
③He was able t leave Germany fr America during the Secnd Wrld War.
④Tm culd sing English sngs at the age f 6.
⑤What can they be ding there?
⑥He can't be in the classrm，fr the light has been turned ff.
⑦It can be quite cld at night here.
⑧—Culd I use yur bike?
—Of curse yu can.
[归纳用法]
(1)表示能力。be able t和can都表示能力，意义上没有区别。但be able t可用于多种时态，而can只有现在式和过去式(culd)。
[名师点津]
was/were able t表示经过一番努力，最后做成了某事；而culd表示过去一般的能力。
(2)表示推测。can表示推测，常用于疑问句和否定句，有时也可用于肯定句表示理论上的可能性，表示“有时候可能会”。culd表示较小的可能性。
(3)表示请求和允许。在问句中，culd比can语气更委婉。
[即学即练1] 选词填空(be able t/can/culd)
①There's smene utside — wh can it be?
②Hwever great the difficulties may be，we can vercme them.
③The fire was very big，but all the peple were able t escape frm it.
④I can nt give yu details because I dn't actually have any details.
⑤Culd I have a wrd with yu，if yu're nt t busy?
2．have t/must
[观察例句]
①Each student has t hand in a cmpsitin nce a week.
②We must d everything step by step.
③Yu dn't have t wrry abut me.I'm a gd swimmer.
④That car is my prperty; yu mustn't use it withut my permissin.
⑤He must be ill.He lks s pale.
⑥If yu must g，at least wait until the strm is ver.
[归纳用法]
(1)have t意为“不得不”，一般指客观，有时态和数的变化；而must意为“必须；应该”，一般指主观，没有时态和数的变化。
(2)have t的否定式意为“不必”，而mustn't表禁止。
(3)must表示推测，意为“一定会”，只能用于肯定句。
(4)if yu must (d sth.)表示虽不赞同但可允许，意为“如果你一定要(那么做)”。
[即学即练2] 选词填空(have t/must)
①She has t d it herself.She has gt n ne t help her.
②They had/have t put ff the sprts meet because f the bad weather.
③Teachers must be patient enugh with their students.
④This bk must nt be remved frm the library.
⑤If yu must smke，please g utside.
3．had better
[观察例句]
①I think yu had better g t the dctr abut yur cugh.
②We had better nt remain here any lnger.
[归纳用法]
had better d sth.意为“最好做某事”，否定形式为had better nt d sth.。
[即学即练3] 翻译句子
①你明天最好早点来。
Yu had better cme early tmrrw.
②你最好别错过末班车。
Yu had better nt miss the last bus.
4．dare/need
[观察例句]
①Yu needn't answer my questin nw.
②Need I tell him everything that has happened t his parents?
③He dared nt tell his parents the truth.
④Dare he g hme alne at night?
⑤He asked me if I dared ride a hrse.
[归纳用法]
need和dare用作情态动词时，主要用于疑问句、否定句和条件从句中，dare有时态变化。另外，need和dare也可用作实义动词。
[即学即练4] 完成句子
①我喜欢周末，因为不必早起。
I lve weekends，because I needn't/dn't need t get up early．
②需要我马上把孩子们召集在一起吗？
Need I gather the children tgether at nce?
③你怎么敢说我是贼呢？
Hw dare yu say I am a thief?
④他问我是否敢摸大象。
He asked me if I dared tuch an elephant．