[语法初识]

原句感知 自主探究 ①Don't bring your cellphone to school.

②Never forget each of us is the master of the earth.

③Turn on the car radio.

④Write to me as soon as possible, will you?

⑤Let's take the underground, shall we?

⑥Let us take care of the house while you are away, will you?

⑦You, girls, clean the desks; you, boys, sweep the floor.

⑧Don't stay outside at night, will you?

⑨Do tell me when to buy the tickets for the concert. 1.①②句为否定祈使句，③④句为肯定祈使句。肯定祈使句以动词原形开头，否定祈使句以don't或never开头。

2．由⑤⑥句可知，let's 的祈使句的反意疑问句用shall we，let us引导的祈使句的反意疑问句用will you。

3．由④⑥⑧句可知祈使句的反意疑问句通常是will you。

4．⑦⑨句中，在祈使句前可加do或you对句子表示强调，以加强句子的语气。 　　

　　[语法剖析]

语法点一 定义 　　

　　祈使句是用来提出命令、请求、建议等的句子。一般不出现主语，谓语动词用原形，句末用句号或感叹号。

　　Be kind to our sisters.

　　对姊妹要和善。

　　Keep quiet, please.

　　请安静。

　　Be careful!

　　当心！

　　Keep off the grass!

　　勿踏草坪！

语法点二 表现形式 　　

　　1．肯定式：以动词原形开头

　　Follow the rules of the road.

　　遵守交通规则。

　　Be sure to get here before nine.

　　一定要九点钟以前到这里。

2．否定式：祈使句的否定式一般是在谓语动词前加do not或don't，有时也用never