内容正文:
第二课时 Section A(Grammar Focus~3c)——单元语法精讲精练
英语 七年级下册 人教版
四清导航
一、定义:用于表达命令、请求、劝告、警告、禁止等含义的句子叫祈使句。祈使句最常用于命令,因此也被称为命令句。祈使句的主语通常为第二人称you,经常省略,故祈使句通常以动词原形开头,也常以“be+形容词”的形式出现。
Please help him.请帮帮他。
Open the door,please.请打开门。
Be careful!当心!
二、否定形式:在动词原形前加don't。
Don't eat here!不要在这里吃东西!
Don't be noisy!别吵!
三、祈使句的其他形式:生活中常有一些表示警告的句子,其结构是“No+v.ing!”或“No+可数名词复数/不可数名词!”意为“禁止……”。
No smoking!禁止抽烟!
No photos!禁止拍照!
四、注意:
以let开头的祈使句,若let后的宾语是us时,其否定形式是在us后面加not;若let后面的宾语是第三人称时,否定形式是在let前面加don't。
Let's not do that again.我们别再那样做了。
Don't let him come in.别让他进来。
情态动词一般不单独作谓语,后面必须接动词原形,与动词原形一起作句子的谓语。
一、must意为“必须;一定”,表示说话人的主观看法以及主观上的必要性,也用于表示命令或感想,没有人称和数的变化。以must开头的一般疑问句,其肯定回答用must,否定回答用needn't或don't have to。mustn't意为“禁止;不允许”。
二、have to意为“不得不”,侧重指客观上的需要,主语是第三人称单数时,用has to。其否定形式是don't have to或doesn't have to。
三、can意为“能;会;可以”,其否定形式是在can的后面加not。
一、用括号内所给单词的适当形式填空。
1.______ (clean) your room after you get up.
2.Please ______ (bring) your dictionary to school next time.
3. ______(not) eat icecream after dinner.
4.No __________ (swim)!
5.She has to ____ (do) her homework when she gets home.
Clean
bring
Don't
swimming
do
二、按要求完成句子。每空一词。
6.You can't play ball games in the classroom.(改为祈使句)
_____ ____ ball games in the classroom.
7.Can we eat in the computer room?(作否定回答)
_____,we______.
8.Amy has to go back home before 9 o'clock at night.(改为一般疑问句)
_____ Amy _____ to go back home before 9 o'clock at night?
9.I have to go to the party this Saturday.(改为否定句)
I _____ _____ __ go to the party this Saturday.
10.I have to bring my dictionary to school next Monday.(对画线部分提问)
_____ do you have to ___ next Monday?
Don't play
No can't
Does
have
don't have to
What
do
eq \x(祈使句)
eq \x(情态动词must,have to与can)
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