動(dòng) 詞
動(dòng)詞是表示動(dòng)作（study, find, swim 等）或狀態(tài)（be, like, feel 等）的詞。動(dòng)詞具有人稱、數(shù)量、時(shí)態(tài)、語(yǔ)態(tài)和語(yǔ)態(tài)變化。
知識(shí)梳理：提綱挈領(lǐng)，抓住重點(diǎn)和難點(diǎn)！
動(dòng)詞分類：動(dòng)詞有助動(dòng)詞、情態(tài)動(dòng)詞、聯(lián)系動(dòng)詞和行為動(dòng)詞四類。
一）助動(dòng)詞
助動(dòng)詞沒有任何含義，不能單獨(dú)做謂語(yǔ)，只能和行為動(dòng)詞一起構(gòu)成謂語(yǔ)，幫助行為動(dòng)詞組成各種時(shí)態(tài)、語(yǔ)態(tài)、語(yǔ)氣以及疑問或否定形式。常見的助動(dòng)詞有be, do, does, did, have, will, shall等。具體用法如下：
1、助動(dòng)詞be的用法如下：
1）構(gòu)成各種進(jìn)行時(shí)態(tài)。如：
It was raining all day yesterday.
昨天整天下雨。
2）構(gòu)成被動(dòng)語(yǔ)態(tài)。如：
The meeting was held yesterday afternoon.
會(huì)議是昨天下午舉行的。
3）與不定式連用表示按照計(jì)劃、預(yù)先安排或規(guī)定要發(fā)生的動(dòng)作。如：
They are to see an English film this evening.
他們今天晚上看英語(yǔ)電影。
2、助動(dòng)詞do的用法如下：
1）構(gòu)成疑問式或否定式。如：
Does he think so?
I didn't say anything about the result.
2)在動(dòng)詞前加上do, does, did表示強(qiáng)調(diào)，意為"的確，確實(shí)"。如：
They do study hard.
She does love him.
He did want to help the old man.
3、have: 助動(dòng)詞have 的過去式是had。have和had均可與動(dòng)詞過去分詞一起構(gòu)成完成時(shí)態(tài)。如：
He has lived here for three years.
As soon as the sun had set they returned.
4、shall, should: 助動(dòng)詞shall只用于第一人稱的將來時(shí)態(tài)；助動(dòng)詞should 是shall的過去式，構(gòu)成過去將來時(shí)。如：I shall send ten letters to my good friend.
She wanted to know if I should go to the palace.
二）情態(tài)動(dòng)詞
情態(tài)動(dòng)詞本身有一定含義，但不能單獨(dú)作謂語(yǔ)，要和行為動(dòng)詞一起構(gòu)成謂語(yǔ)。它們也能表明句子的否定、疑問或時(shí)態(tài)上的區(qū)別。常見的情態(tài)動(dòng)詞有：can, may, must, need, should等。
表示能力
表示能力一般用can, could。如：Rose can speak now, but she couldn't a week ago.
be able to 也表示能力，它和can 的區(qū)別如下：
1）表示做事的能力，兩者可通用。但can 只能用于一般現(xiàn)在時(shí)和一般過去時(shí)。be able to 可用于任何時(shí)態(tài)。如：
She could / was able to eat four pieces of bread when she was young.
They will be able to finish the drawing soon.
2) 表示過去經(jīng)過努力而成功的某一次動(dòng)作，只能用was/were able to, 但在否定句中可互換。如：
She was weak, but was able to finish the task last night.
can (could) 在疑問句中與第二人稱連用時(shí)，表示征求對(duì)方意見或提出請(qǐng)求，表示委婉語(yǔ)氣。雖然could是can的過去式，但是could 只是表示比can語(yǔ)氣更加委婉客氣，沒有時(shí)間上的差別。如：
-Could you lend me your pen?
-Yes, I can.
表示許可
表示許可一般用may/might, can/could, 而且?？苫Q。Might, could語(yǔ)氣比較委婉。要特別注意：回答以might, could開頭的疑問句只能用may, can 給予直截了當(dāng)?shù)幕卮稹?BR> -Might/Could I borrow your book?
-Yes, you may/can.
表示必需、必要
must和have to都有"必須" ，一般情況下可互換。如：You must / have to finish the work..
但他們有如下區(qū)別：
1）must 表示說話人的主觀看法；have to 表示客觀需要。如：
I must have a talk with him.
He has to give up smoking because of badly cough.
2) 否定式mustn't 表示禁止，意為"不準(zhǔn)，不可以做"；don't have to 意為"不必"。如：
You mustn't hit her.
You don't have to explain it to me if you dislike the job.
注：表示推測(cè)的情態(tài)動(dòng)詞有表示"一定"的must, 表示"很有可能"的should, ought to 和表示"可能"的can, could, may, might。具體用法如下：
must 表示較有把握的推測(cè)，只用于肯定句，不能用語(yǔ)否定句或疑問句。用法如下：
1）對(duì)目前動(dòng)作的推測(cè)，用must+動(dòng)詞原形。如：
You must lose in the mountain.
2) 對(duì)目前狀態(tài)的推測(cè)，用must + be + 表語(yǔ)。如：You speak for 4 hours, you must be thirsty.
在肯定句中，表示對(duì)現(xiàn)在或?qū)戆盐詹淮蟮耐茰y(cè)用may (might) +動(dòng)詞原形，might 比 may 的可能性更??；對(duì)過去把握不大的推測(cè)用may (might) have+ 過去分詞。如：
The package might come tomorrow.
They may have killed the enemies.
3、在疑問句中，對(duì)現(xiàn)在表示推測(cè)用can (could) …+動(dòng)詞原形，對(duì)過去表示懷疑則用can (could) …h(huán)ave+過去分詞；在否定句中，對(duì)現(xiàn)在表示推測(cè)用can't+動(dòng)詞原形，對(duì)過去表示推測(cè)用can't (couldn't) have+過去分詞。如：
It can't be John. He has gone to UK.
4、need的雙重身份
need 既可作情態(tài)動(dòng)詞又可作實(shí)意動(dòng)詞，它們的用法不同，如不注意區(qū)分，就容易用錯(cuò)。
三）系動(dòng)詞
連詞動(dòng)詞的種類
聯(lián)系動(dòng)詞含有一定意義，它們要與其后做表語(yǔ)的形容詞、名詞或介詞（短語(yǔ)）一起構(gòu)成合成謂語(yǔ)。系動(dòng)詞按意義可分為三類，而且有自己的特定用法。
1、按意義聯(lián)系動(dòng)詞有：be, appear, seem, keep, remain, continue, stay, prove 等，如：Jim appears very old.
２、表示感覺的聯(lián)系動(dòng)詞有l(wèi)ook, feel, smell, sound, taste等。如：It smells bad.
3、表示轉(zhuǎn)變的聯(lián)系動(dòng)詞有become, fall, get, go, grow, turn等。如：
She becomes more beautiful than three years ago.
四）行為動(dòng)詞
行為動(dòng)詞又稱實(shí)義動(dòng)詞，它們都含有實(shí)在的意義，表示動(dòng)作或狀態(tài)，可在句中獨(dú)立作謂語(yǔ)。行為動(dòng)詞又分為及物動(dòng)詞和不及物動(dòng)詞。
１、及物動(dòng)詞
及物動(dòng)詞后一定要跟賓語(yǔ)，意思才能完整。如：
My mother told me she wanted to buy some books for me.
2、不及物動(dòng)詞
不及物動(dòng)詞意義完整，不需帶賓語(yǔ)，但如果有些不及物動(dòng)詞非要帶賓語(yǔ)時(shí)，必須先加介詞后加賓語(yǔ)。如：
He only worried about his daughter.
二、動(dòng)詞的時(shí)態(tài)
動(dòng)詞的時(shí)態(tài)有很多。初中階段主要掌握八種：一般現(xiàn)在時(shí)、一般過去時(shí)、現(xiàn)在進(jìn)行時(shí)、過去進(jìn)行時(shí)、一般將來時(shí)、過去將來時(shí)、現(xiàn)在完成時(shí)、過去完成時(shí)。
1．一般現(xiàn)在時(shí)
1）一般現(xiàn)在時(shí)態(tài)的構(gòu)成：主語(yǔ)是I, we, you, they和名詞復(fù)數(shù)時(shí)作謂語(yǔ)的行為動(dòng)詞用原形。主語(yǔ)是he, she , it和名詞單數(shù)時(shí)，作謂語(yǔ)的行為動(dòng)詞的詞尾變化如下：
一般情況
＋s
以s, x, ch, sh 或 o結(jié)尾
＋es
以輔音＋y結(jié)尾
去y變i＋es
2）一般現(xiàn)在時(shí)態(tài)的肯定句、否定句和疑問句形式（以be和like為例）：
主 語(yǔ)
肯 定 式
否 定 式
疑 問 式
第一、二人稱和第三人稱復(fù)數(shù)以及名詞復(fù)數(shù)
I am a student.
We/You/ They are students.
He/ She is a student.
I / We/ You/ They/ like music.
Many people like music.
I am not a student.
We/You/ They are not students.
He/ She is not a student.
I / We/ You/ They/ don’t like music.
Many people don’t like music.
Are you a student.
Are you/ they students?
Is he/ she a student?
Do you/ they like music?
Do many people like music?
3）一般現(xiàn)在時(shí)態(tài)的用法：
現(xiàn)階段經(jīng)常性，習(xí)慣性的動(dòng)作 。例如：
I get up at six every morning.
He plays tennis once a week.
現(xiàn)在的狀態(tài) 例如：
My mother is a teacher. She teaches English in a school.
客觀真理 例如：
The earth goes around the sun.
4）常用于一般現(xiàn)在時(shí)態(tài)的時(shí)間狀語(yǔ)：
often usually sometimes always every day never in the morning 等。
例題解析：舉一反三，學(xué)的更輕松！
1. --- May I help you, sir?
--- Yes, I bought the TV the day before yesterday, but it ______.
A. didn't work B. doesn't work C. won't work D. can't work
解析：電視雖然是前天買的， 但壞了是現(xiàn)在的狀態(tài)， 應(yīng)該用一般現(xiàn)在時(shí)態(tài)。選B.
2．______ the bus until it ______..
A. Get off, stops B. Get off, will stop C. Don't get off, stops D. Don't get off, will stop
解析：這是一個(gè)以u(píng)ntil引導(dǎo)的時(shí)間狀語(yǔ)從句，主句是祈使句，因此從句要用一般現(xiàn)在時(shí)表示將要發(fā)生的動(dòng)作。根據(jù)句意此題應(yīng)用not …until（直到……才）句型。應(yīng)選C。
3．The 70-year-old man ______ exercises in the morning.
A. takes B. are taking C. took D. will take
解析："這個(gè)70歲的老人早晨鍛煉。"這里鍛煉是一個(gè)經(jīng)常性、習(xí)慣性的動(dòng)作。因此，應(yīng)選A.