主系表结构讲解

主语：放句首 名词或代词作句首

Book, ruler, father,sister, Jack, Beijing China, books parents, flowers She he they it they

系动词：我用am, 你用are, is用于她他它 其余单数用is 复数用are 表语： 名词或代词 ruler, Jack, they

形容词 interesting， friendly good big small, late red ,green 数字 four

介词短语：in the room, on the desk

陈述句：

例句：

⑴I am a dancer. I’m happy. ⑵He is Jim. He’s tall.

She is Gina. She’s 12 years old. It is my new bag. It’s red.

The bag is in the desk. (单数名词is)

⑶You are a student. You’re young.

The pants are 20 dollars. They’re blue. (复数名词用are)

缩写：am, is, are用在名词或代词后常用缩略形式: ‘m, ‘s, ‘re。not 和其前面的动词也常可缩写成n't（有例外）。

The book is mine I am Jack.

The room is big, Her eyes are small My hair is black I am 12 years old A ball is under the chair

否定句： 在动词后加not

The book is not mine She is not Mary.

缩写形式：isn’t aren’t am 与not 不缩写， 将O变 ’

疑问句: 将系动词直接提前其余不变

Is this your book?

Is Jim a student? Is the table big or small? 回答 It’s big./ It’s small. 回答：肯定回答 Yes, 代词 + be

否定回答 No, 代词+ 否定缩写形式

特别注意问句中的主语是this that 时用it 代替 these those 用they 代替

Are they your books? Are you Jack?