1、情态动词一、情态动词的基本用法(1)观察例句1The police still have not found the lost child，but they are doing all they can.2Our daughter could walk when she was nine months old.3Accidents can happen on such rainy days.4We may go to the cinema tonight，but we are not sure yet.5That might be our taxi but I doubt it.6I coul
2、d do it now，if you like.7Must I give up smoking?8Did she have to pay a fine?归纳用法1表示能力：(1)can 表示现在的能力(如例1)；(2)could表示过去的能力(如例2)。2表示推测：推测即可能性(如例3例6)。3表示必要性：(1)must表示主观上的必要性(如例7)；(2)have to表示客观上的必要性(如例8)。名师点津表示推测的情态动词的用法比较(由强到弱)：情态动词肯定式否定式疑问式must 必定，必然/should按说应该应该不会/ought to按说应该应该不会/can/不可能有可能吗？could微
3、弱的可能不可能语气比can弱may或许，也许，也说不定可能不/might比may还弱比may not还弱/即学即练1用适当的情态动词填空An experienced teacher can also make mistakes.You cant mistake their car；It has got a bright red line all over it.He must be the wanted man.Hes exactly like the one in this picture.I can run faster than you.The question was so hard
4、that he could not answer it.I have to go to the dentist tomorrow.二、 情态动词的基本用法(2)观察例句1What shall we do this weekend?2The candidates shall remain in their seats until all the papers have been collected.3He should be here on time he started early enough.4You can stay here as long as you can，if you will
5、.5She will listen to records alone in her room for hours.6When he was abroad，he would read as many books as possible.7I didnt know whether he dared say that to him.8If she wants anything，she need only ask.归纳用法1shall表示征求意见(如例1)和宣布法律、规定(如例2)。2should意为“按说应该”，表示推测(如例3)，相当于ought to。3will 表示主观的意志、意愿(如例4)
6、及用来叙述目前的习惯(如例5)。4would 用来叙述过去的习惯(如例6)。5dare有时态的变化(如例7)。6need无时态的变化(如例8)。名师点津1shall还可表示说话者给对方的命令、指示或允诺You shall have a new dress for your birthday.你生日会有一条新的裙子。2should还可表示“(义务上的)应该”，在语气上比must (必须)弱。I should go and visit him this afternoon，but I wonder if I will be free.今天下午我应该去看望他，但我不知道我是否有空。3will/wou
7、ld还可表示请求、建议，主语为第二人称，would在语气上更委婉。Will/Would you go with me?你愿意和我一起去吗？4would和used to都可表示过去的习惯，但前者表示过去反复的动作，常与every day，often，frequently等连用；后者表示过去的状态或过去的习惯，但现在已不存在。She doesnt get up so early as she used to.她不像以前那样起得那么早了。5dare作情态动词时，还可用于条件状语从句中。If you ever dare call me that name again，youll be sorry.如果
8、你敢再叫我那个名字，你将会后悔。即学即练2用情态动词填空Shall we order some coffee?He dare not go through the woods.I dont know why you should think that I did it.I still remember my happy childhood when my mother would take me to Disneyland at weekends.Will you send this letter for me，please?三、情态动词的特殊用法表示对过去的推测观察例句1She could
9、have gone out with some friends.2It must have rained last night，for the road is quite muddy.3He might have missed the train.4Where can she have put it?5Its too late.I think he may have gone to bed.归纳用法1must have done sth.表示“(过去)一定做了某事”；语气比较肯定；用于肯定句 (如例2)。 2may have done sth.表示“也许已经做了某事”(如例5)，may not
10、 have done sth.表示也许还没做某事。3might have done sth.表示“过去可能/也许做了某事”；语气不确定；用于肯定句(如例3)。might not have done sth.表示过去也许没做某事。4could have done sth.表示“过去可能做了某事” (如例1)，could not have done sth.表示过去不可能做了某事。5can have done sth.表示“疑虑或惊讶”，用于疑问句 (如例4)，其否定形式为cant/cannot have done sth.。即学即练3完成句子The boy may have known the
11、truth(可能已经知道了事实)，but I am not quite sure.Go and ask him about it.He cant/cannot have forgotten (不可能忘了)it.Dont worry.Your father may not have been hurt seriously(也许伤得不严重)Shes not here.She must have left already(准是走了)四、情态动词的特殊用法表示与过去事实相反观察例句1I neednt have taken the umbrella，for the weather is fine.2I
12、could have worked out the problem，but I was too nervous.3You might have given him more help，though you were busy.4Sorry to hear that you had a bad fall.You should have been more careful.5Im sorry.I shouldnt have lost my temper.归纳用法1could have done sth.表示过去本可以做某事但实际上没做 (如例2)。2neednt have done sth.表示过
13、去本不必做某事但实际上做了(如例1)。3should have done sth.表示过去本应该做某事但实际上没做(如例4)，可与ought to have done 换用。4shouldnt have done sth.表示过去本不应该做某事但实际上做了 (如例5)。5might have done sth.表示过去也许可以做某事但实际上没做(如例3)。即学即练4完成句子We could have faced(本来可以面对) the difficulty together，but you didnt tell me.You neednt have worked(本来不必工作)that lat
14、e last night.The deadline is tomorrow afternoon.You should have come(本应该来) to the conference yesterday.The pills might have helped him(也许可以对他有帮助) but he didnt take them regularly.单句语法填空1You neednt worry about my weekendI always have my plans ready before it comes.2For the engine to work，the green le
15、ver must be in the “up” position.3According to the rule，all the students shall go to school before 8：00 am.4He should not make this mistake，for he had been reminded several times.5You can bring a gift to the hostess，but it neednt be too expensive.6Susans family is very rich and her parents can affor
16、d to send her to China for further study.7Dont worry，Martin.You shall have a new pair of sport shoes tomorrow.8The light in his office is still on.He must be in.9I cant thank you too much for all your help to my son while we were away.10The children must have got(get)lost in the woods；otherwise，they
17、 would have been at the lakeside camp as scheduled.短文语法填空China has become the first country to land a spacecraft on the far side of the moon.The unmanned Change4 probe(探测器)the name was inspired by an ancient Chinese moon goddess 1.touched(touch) down last week in the South PoleAitken basin.Landing o
18、n the moons far side is 2.extremely(extreme) challenging.Because the moons body blocks direct radio communication with a probe，China first had to put a satellite in orbit above the moon in a spot where it 3.could send signals to the spacecraft and to Earth.The far side of the moon is of particular 4
19、.interest(interesting) to scientists because it has a lot of deep craters(环形山)，more so 5.than the familiar near side.Chinese researchers hope to use the instruments onboard Change4 6.to find(find) and study areas of the South PoleAitken basin.“This really excites scientists，”Carle Pieters，a scientis
20、t at Brown University，says，“because it 7.means(mean) we have the chance to obtain information about how the moon 8.is constructed(construct)”Data about the moons composition，such as how much ice and other treasures it contains，9.could help China decide whether 10.its(it) plans for a future lunar(月球的) base are practical.
