英语一般现在时(Simple present tense)。表示通常性、规律性、习惯性、真理性的状态或者动作(有时间规律发生的事件)的一种时间状态。

动词的现在式有am,is,are三种,分别接在不同人称的主语之后:
1.be动词是系动词的一种,表示“……是……”的意思。
现在式(The Present Forms)有am,is,are三种。这三种动词的原形是be,所以它们称为be动词。
2.be动词的现在式
be动词的现在式有am,is,are三种,分别接在不同人称的主语之后:
be动词句型的构成
肯定句:主语 + be动词(am/is/are)...
否定句:主语 + be动词(am/is/are) + not...
疑问句:be动词(am/is/are) + 主语...?
疑问代词/疑问副词 + be动词(am/is/are) + 主语...?
3. be动词的肯定句
句型:主语 + be动词...
be动词的肯定句由“主语 + be动词(am/is/are) + 表语”构成:

I am a doctor.

我是一名医生。

Mary is at work.

玛丽在工作。

He is very brilliant.

他非常聪明。

It is a nice day.

今天天气晴朗。

You are my only friend.

你是我惟一的朋友。

They are students.

他们是学生

4 be动词的否定句
句型:主语 + be动词(am/is/are) + not...
be动词一般现在时的否定句结构,是在be动词am,is,are之后加not:
We aren't her classmates.

我们不是她的同班同学。

I'm not Tom.

我不是汤姆。(I'm是I am的缩写,读作/aim/。)

It's not a cat,but a dog.

这不是猫,而是狗。

Things are not always what they seem(to be).

事物并不总是与表象一致。

be动词否定句的缩写方式:
is not的缩写是isn't,读作/′iznt/;are not的缩写是aren't,读作/a:nt/;I am~的否定句是I am not~,缩写为I'm not~;am not不缩写在一起。
be动词的一般疑问句
句型:be动词 + 主语...?
回答方式:Yes,主语 + be动词(am/is/are)...
No,主语 + be动词(am/is/are) + not...

1.I ______ cooked a meal when you _____ me.

A. cooked, were ringing B. was cooking, rang

C. was cooking, were ringing D. cooked, rang

2.He said he _____ to draw a plane on the blackboard at that time.

A. tries B. tried C. was trying D. will try

3.While she ______ TV, she ______ a sound outside the room.

A. was watching, was hearing B. watched, was hearing

C. watched, heard D. was watching, heard

4.They _____ a football game from 7 to 9 last night.

A. were watching B. watch C. watched D. are watching

5.What book ____ you ______ when I ____ you at four yesterday afternoon?

A. did, read, was seeing B. did, read, saw

C. were, reading, saw D. were, reading, was seeing