英语八上第几单元学的动词不定式（八年级上册英语语法）
英语八上第几单元学的动词不定式（八年级上册英语语法）③定语②宾语③是非谓语动词动词不定式可充当的成分：①主语
一、动词不定式的用法
动词不定式的定义：
①含有动词
②to do(动词原形)结构
③是非谓语动词
动词不定式可充当的成分：
①主语
②宾语
③定语
④状语
⑤宾补
⑥表语
注意：动词不定式是非谓语动词，不能作谓语
（一）动词不定式作主语
作主语，可以用it代替，it叫形式主语，动词不定式放在后面叫真正主语
1．To learn a foreign language is not easy. It is not easy to learn a foreign language.
2. It’s dangerous to drive very fast.
To have a walk is good for you.
散步是对你有益的。
主语 系动词 表语
解析：have a walk(散步)是动词短语，不能直接作主语；To have a walk(散步)是动词不定式，可作主语
（二）动词不定式作宾语
1.如果宾语太长，可用it作形式宾语，构成“主语 谓语 it 宾语补足语(名词或形容词) to do sth”结构，谓语动词常为find、think、feel等。
I think it's too easy to solve this problem.我认为解决这个问题太简单了。
I found it difficult to stop him.
我发现拦截他很困难。
I want to have a walk.
（我）〈想要〉｛去散步｝。
（主语 ）〈谓词〉 ｛宾语｝
解析：动词不定式to have a walk(去散步)是want(想要)的内容，作want(想要)的宾语
2.常可接动词不定式作宾语的动词有：
agree同意／hope希望／decide决定／need需要 /mean打算／wish希望/fail(失败)/ want想要/begin开始/would like想要/Ask请求/beg乞求／leave离开/like/ love喜欢 /hate(讨厌）/prefer宁愿/order命令/teach教/tell／告诉/ believe相信/find／找出 /know／知道／want／想要／ think认为／ understand明白，理解，懂得
3.后面跟动词不定式的动词口诀有：
1）三个希望两答应
wish hope want promis agree
2）两个要求莫拒绝
ask beg refuse
3）想要明白与知道
would like understand know
4）教会告诉要相信
teach tell believe
5）找出爱恨区别点
find love hate
He has decided to go to the countryside. 他已决心去乡下。
4.（1）“疑问词 动词不定式”结构可以作动词know、think、find out等的宾语。I don’t know who to ask. 我真不知道该问谁。
（2）“疑问词 动词不定式”可以作动词show、teach、ask等后面的直接宾语。
She told me where to find the earphone. 她告诉我什么地方可以找到耳机。
5.动词不定式可以作介词的宾语。
Autumn harvest is about to start. 秋收即将开始。
I’m worrying about what to do next. 我正愁下一步该怎么办。
（三）动词不定式作定语
作定语的动词不定式与被修饰词有动宾关系。此时，如果动词不定式的动词为不及物动词，后面的介词绝对不能省略。
动词分“及物”和“不及物”，“及”你就理解成“涉及，有联”，“物”你就理解成“事物或人”。及物的动词”就是“涉及事物的动词”即“有受对象的动词”或“带宾语的动词”（像买buy 花费spend）；“不及物的动词”就是“不带宾语的动词”“没有动作承受对象的动词”（像跑run，跳jump ）。 所以介词不能够省略。
I have a lot of books to read.
我有许多书要读。
We had only a cold room to live in. 我们只有寒室一间。
I have（ some work） to do.
我有（一些工作）要做。
（名词 ）定语
解析：动词不定式to do(要做)限定修饰work(工作)的属性，作work(工作)的定语；注意：动词不定式to do只能作名词代词的后置定语
（四）动词不定式作状语
I come here to see you.
（我）〈来到〉这里来看你。
（主语）〈谓词动词〉 状语
解析：动词不定式to see you(来看你)修饰动词come(来)的目的，作目的状语
（五）动词不定式作宾补
（I ）〈want〉｛ you｝ to join us.
（我）〈想要〉｛你｝加入我们。
（主语）〈谓语〉｛宾语｝ 宾补
解析：动词不定式to join us(加入我们)补充说明you(你)的动作，作you(你)的宾补；
（六）动词不定式作表语
（My dream）〈 is 〉to be a teacher.
（我的梦想）〈是〉当老师。
（主语）〈 系动词〉 表语
解析：动词不定式to be a teacher(当老师)表示My dream的内容，作表语；
（七）区别下列词组的不同含义:
remember to do 记住要做某事
remember doing 记得曾经做过某事
forget to do忘记要做某事
forget doing 忘记曾经做过某事
stop to do 停下来去做某事
stop doing 停止做某事
go on to do 继续做另一件事
go on doing 继续做原来在做的事
（八）It takes sb some time to do sth.花费某人一段时间干某事.
It took me half an hour to do my homework yesterday.昨天我花了半小时做回家作业.
It took Jim an hour and a half to read the book.吉姆花了一个半小时看这本书.
It took mother one and a half hours to do the housework.母亲花了一个半小时干家务.
（九）不定式的特殊句型Why not
"Why not 动词原形"表达向某人提出建议，翻译为："为什么不……?" "干吗不……?"
Why not take a holiday?
干吗不去度假?
二、动词不定式特殊用法
（一）It's for sb.和 It's of sb.
1)lt's ＋形容词＋for sb.
此句型常用于表示事物的特征特点，表示客观形式的形容词，如easy hard difficult interesting impossible等：
It's very hard for him to study two languages.
对他来说学两门外语是很难的。
It’s dangerous for children to swim in the river. 孩子在这条河里游泳很危险。（游泳这件事情危险）。
2)lt's＋形容词＋of sb
此句型一般用来表示人物的性格、品德，表示主观感情或态度的形容词，如good bad polite unkind kind nice clever right wrong careful careless nice clever foolish right等。
lt's foolish of you to do that.
It's very nice of you to help me.
你来帮助我，你真是太好了。
It was careless of you to do that.
你这么做真粗心。（你这个人粗心）。
for 与of 的辨别方法：
用介词后面的代词作主语，用介词前边的形容词作表语，造个句子。如果道理上通顺用of，不通则用for。如：
You are nice.(通顺，所以应用of)。
He is hard.(人是困难的，不通，因此应用for。)
（二）用作介词的to
to 有两种用法：
第一种用法为：不定式 动词原形;
第二种用法为：介词 名词/动名词..
to 在下面的用法中是第二种即to 名词/动名词：
admit to承认
confess to承认
be accustomed to 习惯于
be used to 习惯于
stick to 坚持
turn to开始，着手于
devote oneself to 献身于
be devoted to 致力于
look forward to 盼望
pay attention to 注意
（三）省 略to 的动词不定式
1) 情态动词 ：( 除ought 外，ought to)
2) 使役动词： let have make
3) 感官动词： see watch look at notice observe hear listen to smell feel find 等后作宾补，省略to；
注意：在被动语态中则to 不能省掉。
I saw him clean the classroom.
=He was seen to clean the classroom.
The boss made them work the whole night.
=They were made to work the whole night.
4) would rather，had better；
5) Why… / why not…；
6) help 可带to，也可不带to help sb (to) do sth；
7) but和except：but前是动词do时，后面出现的动词用不带to的动词不定式；
8) 由and or和than连接的两个不定式，第二个to 可以省去；
9) 通常在discover imagine suppose think understand等词后，可以省去to be；
He is supposed (to be) nice. 他应该是个好人。
举例：He wants to move to France and marry the girl.He wants to do nothing but go out.
比较：He wants to do nothing but go out.
He wants to believe anything but to take the medicine.
典型例题
1) ---- I usually go there by train.
---- Why not ___ by boat for a change?
A. to try going B. trying to go
C. to try and go D. try going
答案：
D. why not 后面接不带to 的不定式，因此选D。
2) Paul doesn't have to be made ___.
He always works hard.
A. learn B. to learn C. learned D. learning
答案：
B. make后接不带to 的动词不定式，当其用于被动时，to 不可省略。
（四）动词不定式的否定式。
在不定式标志to前加上not。例如：
Tell him not to shut the window。让他别关窗。
She pretended not to see me when I passed by. 我走过的时候，她假装没看见。
【典型例题】
1）Mrs. Smith warned her daughter ___ after drinking.
A. never to drive B. to never driver
C. never driving D. never drive
答案：A。warn sb to do sth. 的否定形式为warn sb not to do sth. 此处用的是否定词never.
2） The boy wanted to ride his bicycle in the street，but his mother told him ____.
A. not to B. not to do
C. not do it D. do not to
答案：A。not to 为not to do it 的省略形式。可以只用to这个词，而不必重复整个不定式词组。及物动词do后应有宾语，因此也B，D不对。
【动词不定式同步练习】
（一）用所给动词的正确形式填空
1. She said she offered ____ (take) me to the shopping center.
2. They decided ____ (play) tennis against Guangming Middle School.
3. He wanted _____ (watch) the football match at the stadium.
4. My parents plan _____ (visit) my grandparents next weekend.
5. David promised ____ (not be)late for school next time.
（二）根据短文内容，用所给动词的正确形式填空。
A
The radio says it will be sunny this weekend. Diana plans 1.____ (enjoy) the sun on the beach. She wants 2._____ (invite) Lucy to go with her. But Lucy said her parents offered 3._____ (take) her to the cinema. So Lucy wouldn't like 4._____ (go) with Diana. Finally Diana decided 5.______ (go) to the beach alone.
B
Lu Xun is one of the greatest writers of modern China. He was born in Shaoxing Zhejiang Province in 1881. At first Lu Xun hoped 6._____ (help) the Chinese people become healthy and strong so he decided 7.______ (be) a doctor. After a few years he started 8.______ (write) short stories because he wanted 9._____ (teach) people about society. One of his most famous stories is The True Story of Ah Q. It describes the hard life of Ah Q and makes people think about society. In the 1920s people began10. _____ (translate翻译) his work into English.
（三）单项选择
1. I can't tell you what she said. I've promised ____ it a secret.
A. keep B. to keep C. keeping D. kept
2. -- What's your plan for the summer holiday?
-- I decide ____ at home and have a good rest fist.
A. to stay B. staying C. stayed D. stay
3. I was waiting ____ across the road when a car hit a boy suddenly.
A. walk B. walking C. to walk D. walks
4. My parents agree _____ football with my classmates on Sunday afternoon.
A. plays B. to play C. playing D. played
5. -- Dad Can I borrow your camera? I want ____ it to take some photos.
-- Sure. But you must promise _____ after it well.
A. to use; look B. use; to look C. to use; to look D. use; look
（四）翻译下列句子。体会不定式做目的状语的功能。
1. To make it easier for the tigers to live we should protect their home in the wild.
2. We should work hard to stop people killing tigers.
3. Let's find out what else we can do to save as many animals as possible.
4. They do important research to find out the best way to protect animals.
5. They also develop plans to help animals in danger.
同步练习
（一）用所给词的正确形式填空
1. Their parents don't allow them ____(swim) in the river. It's really dangerous.
2. Please tell the boys _____ (not make) any noise. My baby is sleeping.
3. They try to find some more ways to make some animals ____ (work) for people.
4. My friend invited me ____ (watch) Beijing Opera last weekend.
5. I often hear a girl _____ (practise) playing the piano in the classroom.
（二）单项填空
1. We should allow students _____ their own school uniform.
A. choose B. to choose C. choosing D. chose
2. The teacher told Mike ____ too much time playing computer games.
A. not to spend B. to spend C. spent D. not spend
3. Our tour guide advised us ____ far from our camp. It was dangerous.
A. to walk B. not walk C. not walking D. not to walk
4. I saw students ____ when I passed the playground.
A. running B. run C. ran D. to run
5. I help my mother ____ housework every day after I finish homework.
A. doing B. does C. do D. did
6. The boss made his employees ____ over 8 hours a day.
A. working B. work C. works D. to work
7. Our teacher asked us _____ the handcrafts this weekend.
A. to hand in B. hand in C. handing in D. hands in
8. Tony would like his parents ____ him to Shanghai Disneyland this summer holiday.
A. take B. to take C. taking D. takes
9. All the students agreed to choose Han Mei _____ their monitor.
A. being B. is C. to be D. was
10. Mike's parents want him _____ the army after finishing college.
A. to join B. joining C. join D. join
参考答案
（一）用所给动词的正确形式填空
1. to take 依据：offer to do 主动提出做某事
2. to play 依据：decide to do 决定做某事
3. to watch 依据：want to do 想要做某事
4. to visit 依据：plan to do 计划做某事
5. not to be 依据：promise to do 答应做某事，保证做某事
（二）根据短文内容，用所给动词的正确形式填空。
A
1. to enjoy 2. to invite 3.to take 4. to go(解析：would like to do想要做某事） 5. to go
B
6. to help（解析：依据want to do 想要做某事） 7. to be（解析：依据decide to do决定做某事） 8. to write（解析：依据start to do 开始做某事） 9. to teach（解析：依据want to do想要做某事） 10. to translate（解析：依据begin to do 开始做某事）
（三）单项选择
1. B 依据：promise to do 答应做某事
2. A 依据：decide to do决定做某事
3. C 依据：wait to do 等待做某事
4. B 依据：agree to do 同意做某事
5. C 依据: want to do 想要做某事，promise to do 答应做某事
（四）翻译下列句子。体会不定式做目的状语的功能。
1. 为了让老虎更容易地生存， 我们应该保护它们在野外的家。
2. 我们应该努力工作来阻止人们猎杀老虎。
3. 让我们弄清楚我们还能做什么来拯救尽可能多的动物。
4. 他们做重要的研究为的是找出保护动物的最佳方法。
5.他们也制定计划来保护濒危动物。
三：不定式作宾语补足语。
同步练习：
（一）用所给词的正确形式填空
1. to swim依据：allow sb. to do 允许某人做某事。
2. not to make 依据：tell sb. not to do 告诉某人不要做某事。
3. work 依据：make sb. do 使某人做某事
4. to watch 依据：invite sb. to do 邀请某人做某事
5. practice 依据：hear sb. do 听见某人做某事，指听到的是动作的全过程。
（二）单项填空
1. B 依据：allow sb. to do 允许某人做某事。
2. A 依据：tell sb. to do 告诉某人做某事，否定形式是 tell sb. not to do 告诉某人不要做某事。
3. D 依据：advise sb. to do 建议某人做某事。否定形式是：advise sb. not to do建议某人不要做某事。此处应是建议不要远离营地。故选D
4. A 依据：see sb. doing 看见某人正在做某事。句意是：当我从操场旁边路过的时候，看见学生们正在跑步。
5. C 依据：help sb. do 帮助某人做某事。
6. B 依据：make sb. do 让某人做某事。
7. A 依据：ask sb. to do 让某人做某事，要求某人做某事。
8. B 依据: would like sb. to do 想要某人做某事
9. C 依据：choose sb. to do 选择某人做某事
10. A 依据：want sb. to do想要某人做某事
【练一练】
根据括号内的动词 用适当的形式填空 空内可能不只填一个词 使句子完整意思正确
1. They usually __________ kites on Sundays. (fly)
2. Look! The dogs __________ after the cat. (run)
3. Miss Gao __________ English in our school since she came here. (teach)
4. The class meeting _________ last Wednesday afternoon. (hold)
5. You should let him __________ the work by himself. (finish)
6. Meimei __________ to wash the old woman’s clothes twice every week. (go)
7. Mr Jiang __________ us Chinese last term. (teach)
8. My father __________ back from Japan tomorrow. (come)
9. It’s seven o’clock now. The Greens __________ breakfast together. (have)
10. Jim __________ many Chinese songs since he came to China. (learn)
11. Please remember __________ the window when you leave the room. (close)
12. After school some students began to do some __________ in the classroom. (clean)
13. English __________ widely in the whole world today. (speak)
声明：编辑整理自网络，仅供大家学习！
