单数句变复数句是七年级英语试题中的一个题型. 记住以下几要素即可迎刃而解英语复数句子怎么改：

1、人称代词主格单数变成相应的人称代词主格复数英语复数句子怎么改，即I-we; you-you; she/he/it-they

She is a girl. -They are girls.

2、 am, is变为are.

I am a student. We are students.

3、 不定冠词a/an要去掉或者变为some, any(肯定句及希望得到对方肯定回答的疑问句用some, 否定和疑问句用any)如：

He is a boy. They are (some) boys.

4、普通单数名词要变为复数形式。

It is a cat. They are cats.

5、指示代词this, that变为these, those.如：

This is a book. These are books.

6、Man, woman做定语修饰可数名词时，要在“数”上与被修饰名词保持一致，但其他名词修饰名词表示“性质”时，不作变化。如：

This is a woman doctor.

They are women doctors.

This is an ornage tree.

They are ornage trees.

7、反身单词也要变相应的复数形式。

myself-ourselves yourself-yourselves himself/herself/itself-themselves

I am teaching myself computer.

We are teaching ourselves computer.

8、物主代词由单数变复数：

名词性物主代词：mine-ours yours-yours his/hers/its-theirs

形容词性主代词：my-our your-you his/her/its-their

This book is mine.—The books are ours.

This is her pen. – These are their pens.

一般情况下，形容词性物主代词在单数句变复数句时不变。当句中形容词性物主代词与句中的主语一致时，形容词性物主代词应随主语人称的变化而变化，仍要保持一致。

This is my pen. These are my pens.

He likes his bike. They like their bikes.

注意：单数句变为复数句时，句中的形容词、定冠词、副词、疑问词、介词短语和感叹词等保持不变。例如： Who is she? Who are they？

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