一、名词作表语：
Africa is a big continent.
非洲是个大洲。
That remains is a puzzle to me.
这对我还是个难题。
二、代词作表语：
What’s your fax number?
你的`传真号是多少？
Who's your best friend?
你最好的朋友是谁？
三、形容词作表语：
I feel much better today.
我今天感觉好多了。
四、数词作表语：
She was the first to learn about it.
她是第一个知道的人。
五、不定式或ing形式作表语：
Her job is selling computers.
她的工作是销售电脑。
Our next step was to get raw materials ready.
我们下一步是把原料准备好。
六、介词短语作表语：
The patient is out of danger.
病人脱险了。
I don’t feel at ease.
我感到不自在。
七、副词作表语：
The sun is up.
太阳升起来了。
I must be off now.
现在我得走了。