连系动词的分类
(1) 状态系动词：只有be一词。如：
She is always like that. 她总是那样。
I am used to going about alone. 我习惯于独来独往。
These shoes are too tight for me. 这双鞋我穿太小。
(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 always kept silent at meeting. 他开会时总保持沉默。
The door remained closed. 门仍然关着。
We can remain friends. 我们可以继续做朋友。
Please stay seated. 请继续坐着。
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。
The doctor seemed very capable. 那医生似乎很能干。
He appeared quite well. 他显得身体相当好。
He appeared taken aback. 他似乎很吃惊。
She appeared perplexed. 她显得迷惑不解。
(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。
Ice feels cold. 冰感觉起来是凉的。
Silk feels soft and smooth. 丝绸摸起来很柔软平滑。
It sounds a good idea. 这听起来是个好主意。
This food tastes good. 这菜好吃。
(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如：
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(from www.yygrammar.com)。
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。
关于连系动词后接不定式的问题
连系动词 be 后根据情况可自由地接不定式作表语：
My dream is to be a scientist. 我的梦想是当一名科学家。
All you have to do is to listen. 你只需要听。
seem, appear, prove, turn out, grow 等连系动词后也可接不定式(尤其是 to be)短语作表语：
The man seemed to be ill. 这个人好像病了。
The plan proved to be useful. 这个计划证明是有用的。
He appears to know this. 他好像知道这一点。
The weather turned out to be fine. 天气结果很好。
He has grown to like studying English. 他渐渐喜欢学英语了。
若所接不定式为to be，通常可以省略。
sound, smell, feel, taste, become 等连系动词后通常不能接不定式：
误：These oranges taste to be good. (应去掉 to be)
误：The roses smell to be nice. (应去掉 to be)
连系动词look后有时也可接to be，但以省略to be 为普通。