祈使句是表示請求、命令、勸告、祝愿或建議的句子。祈使句的主語一般為第二人稱，但往往省去不用。同學們在學習祈使句時應注意以下幾點：

一、祈使句謂語用何動詞形式

英語祈使句的謂語總是用動詞原形。

如：

Be quiet!

別說話!

Come earlier next time.

下次早點來。

Have a good time.

愿你玩得痛快。

Go and tell her.

去告訴她吧。

注：有時為了加強語氣，可在動詞前加do。

如：

Do be careful. 務請小心。

Do come on time. 務必請準時來。

二、肯定祈使句如何變成否定祈使句

祈使句否定式的構成方法是在動詞原形前加don’t：

Don’t be late. 不要遲到。

Don’t speak so loud. 別這么大聲說話。

三、與please連用以使語氣委婉

為使語氣委婉，通常將祈使句與please連用。Please可用于祈使句的句首(其后通常不用逗號)或句末(其前通常用逗號)。如：

Please try to be quiet. 請設法保持安靜。

Please repeat what you’ve just said. 請把你剛才說的話重復一遍。

四、關于以let開頭的祈使句

Let me show you how to do it. 我來告訴你怎樣做。

Let every man do his best. 讓每個人人盡其才。

注意：

1. 這類祈使句的否定式有兩種形式如：

Let’s not hurry. / Don’t let’s hurry. 我們不要太急。

2. let后用作賓語補足語的動詞要用原形，不能用帶to的不定式。

五、祈使句的反意疑問句形式

1. 在通常情況下，若陳述部分為祈使句，反意疑問句通常用will you, won’t you, would you

Turn on the TV, will you? 把電視打開，好嗎?

Tell me the truth, won’t you? 告訴我實話，好嗎?

注：若陳述部分為否定式，則反意疑問句部分只用will you。如：

Don’t forget to post the letter, will you? 請別忘了寄信。

2. 若陳述部分為以 let開頭的祈使句，則要分兩種情況：

(1) 表示請求時，用will you?

Let us know your address, will you? 把你的地址告訴我們吧，好嗎?

(2) 表示建議時，用shall we?

Let’s all sit under this tree, shall we? 咱們都坐在這棵樹下，好不好？

Practice today:

Error Correction

1．A majority of the reports received from people claiming

to have seen the lengendaiy Loch Ness monster have

proven to be mistakes, misconceptions, or tricked. ___________

2. Your semester grade is based not only on how well you

do on each test, but also how you participate in class. ___________

3. Modern sience was born when Galileo began trying to explain

how things happen and thus originating the method of controlled __________

experiment which now forms the basis of scientific investigation

4. Restrict your self to one or two pages, and listing ___________

any publications or referees on a separate sheet.

5. The House proposal would have barred the federal

government from demanding library records, read lists, __________

book customer lists and other material in terrorism and

intelligence investigations.

答案與解析：

1. tricked -> tricks

并列連詞or連接三項成分。前兩項均為名詞，故tricked應改為名詞tricks與前面的mistakes和misconceptions平行。

2. how前加on

3. originating -> originated

And后面的thus說明并列句的第二部分是和前面的began對應，而非與trying對應。

4. listing -> list

這句是祈使句，list與前面的restrict并列。

5. read -> reading