English clauses always have a subject: 英语句子总是只有一个主语

His father has just retired. Was a teacher. > He was a teacher.

I’m waiting for my wife. Is late. > She is late.

Look at the time! Is half past two.> It’s half past two.

except for the imperative 除了祈使句

Go away.

Play it again please.

If we have no other subject we use there or it. 如果没有别的主语，我们可以用there或者it。

there

（1）• to introduce a new topic: 介绍一个新话题

There is a meeting this evening. It will start at seven.

There has been an accident. I hope no one is hurt.

（2）• with numbers or quantities: 关于数字或数量

There was a lot of rain last night.

There must have been more than five hundred in the audience.

（3）• to say where something is: 介绍某物在哪里

There used to be a playground at the end of the street.

There are fairies at the bottom of the garden.

I wonder if there will be anyone at home.

It

We use it to talk about: 我们用it去谈论

（1）• times and dates: 时间和日期

It’s nearly one o’clock.

It’s my birthday.

（2）• weather: 天气

It’s raining.

It’s a lovely day.

It was getting cold.

（3）• to give an opinion about a place: 说一个关于某地的意见

It’s very cold in here.

It will be nice when we get home.

It’s very comfortable in my new apartment.

Using "it" to talk about people 用it谈论人们

（1）• on the telephone: 讲电话时

Hello. It’s George.

（2）• when people cannot see us: 当人们看不到我们时

[Mary knocks on door] It’s me. It’s Mary.

We use it to talk about other people:

（1）• when we point them out for the first time: 当我们第一次指出别人时

Look. It’s Sir Paul McCartney.

Who’s that? I think it’s John’s brother.

（2）• when we cannot see them and we ask them for their name: 当我们第一次问别人名字时

[telephone rings, we pick it up] Hello. Who is it?

[someone knocks on door. We say:] Who is it?