初一英语怎样句式变换像否定句,肯定句,疑问句,复数等等

初一英语怎样句式变换
像否定句,肯定句,疑问句,复数等等

1．肯定句变否定句
肯定句变否定句一般由否定词not来否定句中谓语.初一竞赛范围涉及be动词（is,am,are）,情态动词can,部分实义动词（不包括第三人称单数）等.
（1）凡是含有be（is,am,are）,can的句子,变否定句时,一律在is,am,are,can后加not,即：am not,is not,are not,cannot（cannot一般不分开写）.除am not不可以用缩写式外,其它均可用缩写式,即：isn't,aren't,can't.如：
This is a car．→This is not（isn't）a car．
Those are birds．→Those are not（aren't）birds．
I am a student．→I am not a student．
We are Young Pioneers．→We are not（aren't）Young Pioneers．
She is my friend．→She is not（isn't）my friend．
There is a clock on the table．→There is not（isn't）a clock on the table．
I can see the boat on the river．→I can't see the boat on the river．
（2）祈使句的否定式一般是在祈使句前加don't.如：
Do it like that!→Don't do it like that!
Put on that coat．→Don't put on that coat．
（3）实义动词（不含第三人称单数）的否定式,是在实义动词前加don't构成.如：
I know it．→I don't know it．
I think so．→I don't think so．
I want to put it on．→I don't want to put it on．
2．陈述句变一般疑问句
陈述句变一般疑问句时,凡含有is,am,are,can的句子,将这些词前移至句首（第一个字母大写）,句尾的“．”改为“?”即可.如：
Her skirt is red．→Is her skirt red?
I am in this classroom．→Am I in this classroom?
They are in Class One．→Are they in Class One?
These are football socks．→Are these football socks?
She can swim．→Can she swim
There are some flowers behind the house．→Are there any flowers behind the house?
注意：some一般用于肯定句,any用于否定句和疑问句.含实义动词（不含第三人称单数）的句子变一般疑问句时,是在句首加do.如：
I want a go．→Do you want a go?
I have a sharpener．→Do you have a sharpener?
3．就一般疑问句回答问题
对一般疑问句的回答,肯定回答用yes,否定回答用no.yes后接“主语＋is（am,are,can,do）”；no后接“主语＋isn't（am not,aren't,can't,don't）”.在答语中,原名词主语改为代词he,she,they等；指示代词主语this,that改为it；these,those改为they.如：
—Are you a teacher?—Yes,I am．（No,I am not．）
—Is M ary in our class?—Yes,she is．（No,she isn't．）
—Are these books yours?—Yes,they are．（No,they aren't．）
—Is there a man under the tree?—Yes,there is．（No,there isn't．）
—Can you look after my sister?—Yes,I can．（No,Ican't．）
4．单数句变复数句
单数句变复数句涉及名词和动词的人称和数,人称代词、物主代词、指示代词的人称和数的问题.单数句变为复数句时,上述各类词都要做相应变化,其它词类不变.如：
This is my pencil-box．→These are our pencil-boxes．
That book is mine．→Those books are ours．
He is her teacher．→They are their teachers．
语法
1.一般过去时
定义：过去发生的动作或状态
标志词：in the past … two days ago
yesterday last night
句型转换：
肯定句：主+动词过去式+其它
In the past,people liked travelling by bus
过去人们喜欢乘公交车旅行.
否定句：主+didn’t+动词原形+其它
He didn’t play football last year.他去年不玩足球.
一般疑问句：Did+主+动词原形+其它
Did he play football yesterday?他昨天玩足球了吗?
2.There be 句型的过去时及将来时
过去时：There was/were There was a tree in front of the house last year.
将来时：There will be There will be more trees in the park in 5 years’ time.