Question

2、Be动词的形式和用法

Answer 1

be，is，am，are，was，were，being，been

例句：

The man is back.

They are back.

He was back.

They were back.

They have been back.他们已经回来了。

后面接名词、形容词、地点副词或短语作补足语。

The man is a teacher. 

    a teacher 为补足语，对man的补充说明。

    is为连接主语和补足语的成分。

Mary's new dresses are colorful. 玛丽的新裙子是五颜六色的。

    同上，colorful为补足语

My mother was in the kitchen.我的妈妈再厨房里。

他们是老师。They are teachers.

他以前是一名老师。He was a teacher before.

他已经当了3年的老师。He has been a teacher for 3 years.

在 am，is，are，was，were后面加not。

缩略式 am not，isn't，aren't，wasn't，weren't。

am，is，are是现在时，was，were为过去时。

The man isn't back. 那个男人没有回来。

I am not back. 我没有回来。

They aren't back. 他们没有回来。

以上为现在时

He wasn't back. 他没有回来。

They weren't back.他们没有回来。

以上为过去时

be动词变疑问句，把be动词提到句首，其他成分保持不变。

Is he a teacher?  Yes,he is./No,he isn't.

他是一名老师吗？是的，他是。/不，他不是。

Are you a teacher? Yes,I am./No,I am not.

你是一名老师吗？是的，我是。/不，我不是。

Were they teachers? Yes,they were./No,they weren't.

他们以前是老师吗？是的，他们是。/不，他们不是。

练习：

1、他是医生吗？Is he a docotor?

        不，他不是。No,he isn't.

2、他们昨天在教室吗？Were they in the classroom yesterday?

        是的，他们在。Yes,they were.

他们昨天不在教室。

答案：They weren't in the classroom yesterday.