come和go也可以作系动词，亦称连系动词（link verb），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，用以说明主语的状况、性质、特征等。
come和go也可以作连系动词；其用法如下：
come 和 go 都可用作连系动词，表示事物状态的变化。“变为，成为”。两者之后所接形容词通常各有其特点，有时还可从好坏方面去区别：即 go 用于一种由强到弱或由好到坏的变化，come用于则主要指向好的方面变化。如：
It comes cheaper if you have a season ticket. 如果有一张月票会便宜些。
Fruit quickly goes rotten in hot weather. 天热水果很快会腐烂。
The meat has gone bad. 这肉变味了。
The heat has caused the milk to go sour. 酷热的天气使牛奶酸了。
The meat’s gone off (gone bad). 肉变味(变坏)了。
These apples have gone bad. 这些苹果变坏了。
The radio’s gone wrong. 收音机出毛病了。
Her mother has gone mad. 她母亲疯了。
How can millions of dollars go astray?
几百万美元怎么可能不翼而飞呢？
We locked up our valuables so they would not go astray.
我们把贵重物品锁了起来以免被盗。
Fortunately the gunman's shots went astray.
幸好持枪歹徒把子弹打偏了。
Her wish came true. 她的愿望实现了。
My dream has come true. 我的梦想实现了。
I’ll make all your dreams come true. 我会使你的梦想都成为现实。
The city starts to come alive after dark. 这座城市天黑后便变得热闹起来。
Everything came right. 一切顺利。
Wrong never comes right. 错的永远不会变成对的。
Your shoe-laces have come undone. 你的鞋带散了。
The package is about to come unwrapped. 那个包快散开了。
The meat has gone bad. 这肉变味了。
The children went wild with excitement. 孩子们欣喜若狂。
She went pale at the news. 听了这消息她脸色变得苍白。
He went mad in the end. 最后他疯了。
The children went wild with excitement. 孩子们欣喜若狂。
Fish soon goes bad in hot weather. 大热天鱼很容易坏。
The children must not go hungry. 孩子们不应挨饿。
Something has gone wrong with the radio. 这收音机什么地方出了毛病。
Things will come right. 一切会顺利地进行。
Everything came right. 一切顺利。
Her dream has come true. 她的梦想实现了。
表示人的生理变化通常用 go。如：
go blind 变瞎
go deaf 变聋
go bald 变秃
go grey 两鬓渐白
go还可用于人或事物颜色的变色，与turn用法相同：
She went [turned] blue with cold. 她冻得脸色发青了。
She went red.
她走红了。
The rotten meat went green. 这块腐烂的肉变绿了。
Leaves go [turn] brown in autumn. 秋季树叶变黄。
She went [turned] pale at the news. 她听到这个消息脸色变得苍白。
His hair was going [turning] grey. 他的头发慢慢地变白了。
【注意】
① 但是 go 一般不与 old, tired, ill 等连用，遇此情况要用其他连系动词：grow [get] old 变老，fall [become] ill (sick) 生病，get [feel] tired 疲劳
② go后接形容词通常表示的结果，在个别搭配中也表示现状：go hungry 挨饿，go naked 光着身子
The children must not go hungry. 孩子们不应当挨饿。
He went naked on the street yesterday.
昨天他赤身裸体的在街上走。
③ come 除表示向好的方面变化外，还有以下常见搭配值得注意：come untied 解开，come loose 变松，come undone 松开
The knot has come untied.
扣儿开了。
Your shoe-laces have come undone. 你的鞋带散了。
The package is about to come unwrapped. 那个包快散开了。
The handle has come loose. 这个把柄松了。
This envelope has come unstuck. 这封信开了。
语言习惯仅仅只是习惯，但是，也有例外：
It was tight schedule but everything went right for us.
时间表订得很紧，但一切进行得很顺利。
Says Nixon, “When the polls go good for me….”
尼克松说：“如果投票结果对我有利的话……”