系动词可接哪些词语作表语
连系动词后的表语通常是名词和形容词，有时也可以是代词、数词、副词、介词短语、不定式、动名词、从句等。如：
1. 用名词作表语。如：
Translation is an art. 翻译是一种艺术。
Beijing is a beautiful city. 北京是一座美丽的城市。
2. 用形容词表作语。如：
Traveling is interesting but tiring. 旅行是有趣的，但是使人疲劳。
Every hour and every minute is important. 每一小时，每一分钟，都很宝贵。
3. 用代词作表语。如：
My idea is this. 我的想法是这样的。
Money isn’t everything. 金钱不是一切。
His latest play is nothing. 他最近出的那个剧本毫无价值。
4. 用数词作表语。如：
Tom is 14. 汤姆14岁。
Last check-in time is 20:15. 最后检票时间为20点15分。
The average of letters received each month is 3,000. 每月平均收到信件3,000封。
5. 用副词作表语。如：
The secret is out. 机密泄漏了。
Sales are down. 销售量下降了。
She is off on Saturday. 她星期六不工作。
6. 用介词短语作表语。如：
Dinner is at six. 6点钟开饭。
I hope he is on time. 我希望他准时。
Martha still is in hospital. 马撒还在医院里。
Diana was with the children. 戴安娜和孩子们在一起。
You look like your sister. 你模样像你姐姐。
7. 用不定式作表语。如：
His goal is to be a doctor. 他的目标是当医生。
My duty is to protect my sisters. 我的职责是保护我的妹妹们。
My advice to you is to speak the truth. 我对你的忠告是讲真话。
My dream is to travel around the world. 我的梦想是环游世界。
8. 用动名词作表语。如：
Her hobby is growing roses. 她的爱好是种植玫瑰。
His job is looking after sheep. 他的任务是看羊。
My favorite sport is swimming. 我最喜欢的运动是游泳。
9. 用从句作表语。如：
That’s what we are here for. 我们来这里就为了这个。
The question is how he did it. 问题是他是如何做此事的。
That’s where I first met her. 那就是我第一次遇见她的地方。
The trouble is that I have lost his address. 麻烦的是我把他的地址丢了。