动词
动词是表示动作或状态的词。大多数动词有五种形态，分别是：原形、第三人称单数形式、过去式、过去分词、现在分词。
一分类
根据动词在句中的功能，可将其分为四类，分别是：实义动词（Notional V erb）、连系动词/系动词（Link V erb）、助动词（Auxiliary V erb）、情态动词（Modal V erb）。
1.实义动词：能独立作谓语的动词。根据其功能可分为及物动词（Transitive V erb；
缩写形式为vt.）和不及物动词（Intransitive V erb；缩写形式vi.）。及物动词通常可直接接宾语。不及物动词通常不能直接接宾语。例如：
I bought a book yesterday.
The sun ris in the east.
但很多动词既可作及物动词又可作不及物动词。例如：
Tigers eat meat. ----------- We eat at six.
She’s studying English. --------------- She studies hard.
She can dance and sing. ------------- She can sing many English songs.
2.连系动词/系动词：系动词本身有词义，但不能单独用作谓语，后边必须跟表语，构成系
表结构说明主语的身份、状况、性质、特征等情况。
系动词亦称联系动词（Link V erb），作为系动词，它本身有词义，但不能单独用作谓语，后边必须跟表语，构成系表结构说明主语的身份、状况、性质、特征等情况。
1）状态系动词：用来表示主语的状态，通常是be。例如：老挝旅游安全吗
He is at home now.
2）持续系动词：用来表示主语继续或保持一种状况或态度，主要有keep, remain, stay, lie, rest 等。例如：
He always kept silent at meeting.
This matter rests a mystery.此事仍是一个谜。
The window stayed open all the night.
Peter became a judge but John remained a farmer.
3）表像系动词：常用来表示"看起来……"“好像”，主要有em, appear, look等。例如：
He looks tired.
He ems (to be) very sad.他看起来很伤心。
It appears (to be ) a true story.这似乎是真的。
He appears quite old.他显得老。/ 他看上去很老。
4）感官系动词：感官系动词主要有feel, sound, taste, smell等。例如：
This kind of cloth feels very soft.
This flower smells very sweet.
I feel happy/ good.
5）变化系动词：这些系动词表示主语变成什么/什么样，变化系动词主要有become, grow, turn, fall, get, go, come, run等。例如：
He became mad after that.自那之后，他疯了。
She grew rich within a short time.她没多久就富了。
It will get cooler and cooler when autumn comes.进入秋天后会越来越凉爽。
The well has run dry.这口井干涸了。
6）终止系动词：表示主语已终止动作，常用来表达"证明是"，"结果是"等意思，主要有prove, turn out等。例如：
The rumor proved (to be) fal.这谣言证实是假的。
His plan turned out (to be) a success.他的计划成功了。（turn out表终止性结果）
注：有些系动词还可以是实义动词。例如：
He fell ill yesterday.
他昨天病了。（fell是系动词，后跟表语，说明主语情况。）汽车用品品牌
He fell off the ladder.
他从梯子上摔下来。（fell是实义动词：“摔倒、跌落”。）
3.助动词：助动词本身没有词义，不能单独做谓语。它们在句中与实义动词一起构成各种
时态、语态、语气以及否定和疑问结构等。
1）表示时态。
He is singing.他在唱歌。
English has been taught in China for many years.
舌苔厚白是什么原因2）表示语态。
He was nt to England.他被派往英国。
益母草的禁忌
3）加强语气。
Do come to the party tomorrow evening. 明天晚上一定来参加晚会。
He did know that.他的确知道那件事。
4）构成否定。
I don't like wine.
He doesn't like porridge..
5)构成疑问。
Do you like college life? 你喜欢大学生活吗？
Will you plea give an answer?
Do you believe it, can you receive it?
注：1）比较常用的助动词有：be, have, do, shall, will, should, would等。
2）有些动词可以兼具不同属性；需具体问题具体分析。
We are having a meeting.我们正在开会。（having是实义动词。）
He has gone to New Y ork.他已去纽约。（has是助动词。）
We are having a meeting.(are 是助动词)
We are Chine.（are 是系动词）。
董大力4. 情态动词
情态动词用来表达特定的感情或意义。本身有一定的词义，但不能单独作谓语，须和实义动词一起构成谓语。无人称和数的变化。
1）．can
①表能力（能/能够）。
can表能力时意味着凭体力或脑力或技术等可以无甚阻力地去做某事。
I can speak English.
He is only four , but he can read. 他只有4岁，但已认得字了。
Fire can’t destroy gold. 火烧不毁金子。
注：can 只有一般时和过去时；而be able to 可用于各种时态.例如：
努力学习的壁纸Y ou will be able to skate after you have practid it two or three times.梦到流鼻血
He was able to go to the party yesterday evening and he enjoyed himlf very much.
can常表示一贯的能力，be able to表示客观能力和通过努力可以达到的能力
I can’t swim. But I am sure I will be able to swim through more practic ing.
The fire spread through the hotel, but everyone was able to get out.
②表推测---可能性。
Can the news be true? 这消息可能是真的吗？
It can’t be true. 它不可能是真的。
can 用在肯定句中表示理论上的可能性（潜在的可能）。
Seeing a film can be very exciting.
may 在肯定句中表示现实的可能性。
The road may be blocked. 这条路可能不通了。
③表示许可或请求。
Can I come in ?
Can I smoke here ?
Y ou can’t park here.
could与can的用法基本类似，但可表示委婉客气的提出问题或陈述看法
----Could I u your bike?
----Y es, you can.
I’m afraid I couldn’t give you an answer today.
The teacher said you could go to the store for sweets.
④短语
can but do 只得I can but do my duty.
cannot but do 不得不I cannot but tell him the truth.
cannot help doing 不得不，禁不住I cannot help liking him though he is a naught boy. cannot help but do 不得不I could not help but realize that I was wrong this time.
cannot …… too 无论怎样…… 都不过分. 越……越好。
We cannot prai him too much .
Y ou cannot be too careful.
2）may/might 的用法
①表示请求、允许（可以）。
Y ou may u my bike.
----May I come in?
----Y es, you may.
为什么喜欢----No,you can’t /mustn’t.
② may 表示推测（也许、可能）。
He may be right.
He may not come today (可能不)------ He can not come today.(不可能)
