非凡疑问句：疑问词一般疑问句。如：

Where is my bike?

2.行为动词的变化。

否定句：主语don't( doesn't ) 动词原形( 其它)。如：

I don't like bread. 

当主语为第三人称单数时，要用doesn't构成否定句。如：

He doesn't often play. 

一般疑问句：Do( Does ) 主语 动词原形 其它。如：

- Do you often play football?

- Yes, I do. / No, I don't. 

当主语为第三人称单数时，要用does构成一般疑问句。如：

 - Does she go to work by bike?

- Yes, she does. / No, she doesn't.

2.行为动词的变化。

否定句：主语 don't( doesn't )  动词原形( 其它)。如：

I don't like bread. 

当主语为第三人称单数时，要用doesn't构成否定句。如：

 He doesn't often play. 

一般疑问句：Do( Does )  主语 动词原形

其它。如：

- Do you often play football?

- Yes, I do. / No, I don't. 

当主语为第三人称单数时，要用does构成一般疑问句。如：

- Does she go to work by bike?

- Yes, she does. / No, she doesn't.

动词s的变化规则

1．一般情况下，直接加-s，如：

cook-cooks, milk-milks 

2．以s. x. sh. ch. o结尾，加-es，如：

guess-guesses, wash-washes, watch-watches, go-goes

3．以“辅音字母y”结尾，变y为i, 再加-es，如：

study-studies