句中没有“是 有 将”；
注：“是”指的是be 动词，它包括了am , is , are , was , were ，这五种形式，两种时态学生比较容易掌握。
A : You are a student, aren’t you ?
You aren’t a student .
Are you a student ?
She was late yesterday, wasn’t she ?
Was she late yesterday ?
B : “有” have , has , had ，用于现在完成时和过去完成时，例如： I have been to Beijing before.
I haven’t been to Beijing before.
She has never been to Beijing before.
He had finished his homework before his mother came back.
找准了助动词 have, has , had 问题也就迎刃而解了。要交代学生
C : “将”字指的是 will, shall ,would, should, 找准了这几个词变疑问句，否定句也就不难了。
There will be a meeting this afternoon, won’t there ?
There will not be a meeting this afternoon.
Will there be a meeting this afternoon ?
D 句中有情态动词时，变化方法和以上诸项一样。（ must, can ,may ,need etc ）
We must finish our home work on time , 否定句 must 后加 not ,疑问句 must 提前。
第五点:也是最至关重要的一点，当句中即没有“是”“有”“将”也没有情态动词时，要看原句时态，初一阶段只出现了现在时，那就选 do ,单三人称 does, 初二年级出现过去时，那就选 did ，现举例如下：
1、I like English very much.
Do you like English very much ?
I don’t like like English very much .
2、She goes to school on foot.
Does she go to school on foot ?
She doesn’t go to school on foot.
3、He studied in No. I Middle School last term., Did he study in No I Middle school last term ? He didn’t study in ……