连系动词,它本身有词义,但不能单独用作谓语,后边必须跟表语（亦称补语）,构成系表结构说明主语的状况、性质、特征等情况.表语通常由名词、形容词,或相当于名词或形容词的词或短语等充当,说明主语是什么或怎么样.
一 连系动词的类型
可分为六类：状态系动词、持续系动词、表像系动词、感官系动词、变化系动词、终止系动词.
(1) 状态系动词：只有be一词.如：
She is always like that. 她总是那样.
(2) 持续系动词：表示主语继续或保持一种状况或态度,主要有keep, remain, stay, rest, lie, stand.如：
I hope you’ll keep fit. 我希望你身体好.
He stayed single. 他仍然是单身.
(3) 表像系动词：表示“看起来好像”,主要有seem, appear, look等.如：
He looks tired. 他看起来很累.
He seems (to be) quite happy. 他好像很快活.
(4) 感官系动词：表示“……起来”,有feel(摸起来,感觉) , smell(闻起来) , sound(听起来) , taste(尝起来,吃起来) 等.如：
This kind of cloth feels very soft. 这种布摸起来很软.
He looks honest, but actually he’s a rogue. 他看起来很老实,实际他是一个坏蛋.
They all look alike to me. 他们的模样我看起来都一样.
Everybody feels contented. 每个人都感到很满足.
(5) 变化系动词：表示主语变成什么样,主要有become, grow, turn, fall, get, go, come, run 这个不太好理解,多来点例句.
He became mad after that. 自那之后,他疯了.
She had grown thinner and thinner. 她越来越瘦了.
His cold was growing worse. 他的感冒越来越严重了.
She’s growing fat. 她正在发胖.
He’s grown used to it. 他对此已经习惯.
When she saw this, she turned red. 她看到这,脸红了.
His hair turned grey in a few weeks. 在几个星期中他头发就变灰白了.
The milk will soon turn sour. 牛奶很快就会变酸.
Several people fell ill, victims of blood poisoning. 几个人生病了,都是血中毒的受害者.
We get wiser as we get old. 随着年岁的增长,我们也变得聪明些了.
Your hair has gone quite white! 你的头发全白了!
She went pale at the news. 听到这消息,她脸色变得苍白.
When I mentioned it to him he went red. 我对他提及此事时他脸红了.
He went mad. 他疯了.
The children must not go hungry. 孩子们不能挨饿.
(6) 终止系动词：主要有prove, turn out(结果是,证明是) 等.如：
His story proved false. 他讲的情况原来是假的.
His advice proved sound. 他的劝告证明是对的.
My intuition turned out to be correct. 我的直觉证明是对的.
二 注意事项
1. 有些连系动词通常不用于被动语态和进行时态中.如:feel, taste等词.例如:
-Do you like the material?
-Yes, it feels very soft.
2. 一般情况下,连系动词主要跟形容词或分词作表语.例如:
Be careful when you cross this very busy street. If not, you may get run over by a car.
3. 能跟名词作表语的连系动词常见的有:be, become, appear, seem, prove, remain和turn等.注意:turn后跟(表示主语身份的)名词作表语时,不加冠词.例如:
Twenty years later, he turned teacher.
The population growth in China remains a problem.
4. 连系动词也可跟不定式(to do / to be),常见的有:appear, seem, remain, prove, look等.例如:
Having a trip abroad is certainly good for the old couple, but it remains to be seen whether they will enjoy it.
On the long journey, Peter proved to be a most interesting guide. We all had a wonderful time.
表语是用来说明主语的身份、性质、品性、特征和状态的,表语常由名词、形容词、副词、介词短语、不定式、动词的-ing、从句来充当,它常位于连系动词（be, become, appear, seem等）之后.
例子
Africa is a big continent.
非洲是个大洲.
That remains a puzzle to me.
对我来说,那是一个残余的难题.
编辑本段
具体分析
主语
是一个句子中所要表达描述的对象.
主语可以由名词,代词,数词,动词不定式,动名词,名词化形容词,分词,从句,短语等来担任.
谓语
谓语是用来说明主语做了什么动作或处在什么状态.谓语可以由动词来担任,一般放在主语的后面.
表语
表语是用来说明主语的性质,身份,特征和状态.表语须和连系动词一起构成句子的复合谓语.表语一般放在系动词之后.表语可以由名词,形容词或起名词和形容词作用的词和短语担任.
宾语
是谓语动作所涉及的对象,它是动作的承受者,宾语可以由名词或起名词作用的成分担任,宾语一般放在谓语动词后面.
有些及物动词可以有两个宾语,其中一个宾语多指人,另一个宾语指物,指人的宾语叫做间接宾语,指物的宾语叫做直接宾语,可以带两个宾语的动词有bring,give,show,send,pass,tell等.间接宾语一般放在直接宾语的前面,如果强调直接宾语可把直接宾语放在间接宾语的前面,但间接宾语前须加"to".
有些及物动词除跟一个宾语外,还需要加上宾语补足语,否则意思不完整,它们一起构成复合宾语,复合宾语中宾语和后面的宾语补足语有一种逻辑上的主谓关系,这也是判断是两个宾语还是复合宾语的依据,宾语可以由名词或起名词作用的词担任.
定语
用于描述名词,代词,短语或从句的性质,特征范围等情况的词叫做定语,定语可以由名词,形容词和起名词和形容词作用的词,短语担任.如果定语是单个词,定语放在被修饰词的前面,如果是词组,定语放在被修饰词的后面.
状语
说明事物发生的时间,地点,原因,目的,结果方式,条件或伴随情况,程度等情况的词叫状语.状语可以由副词,短语以及从句来担任.
