Unit4 Don’t eat in class.
Section A（Grammar Focus-3c）
A Trip in London
How can we walk to the bus?
keep the rules.
break the rules.
遵守规则
违反规则
When taking a trip,
we have to
we can’t
follow the rules.
The 1st Stop Winsor Castle
No smoking!
Don’t smoke.
No parking here!
Don’t park here.
Write the rules for the school library.
Library Rules
1. __________________________________
2. __________________________________
3. __________________________________
4. __________________________________
Don’t talk.
Don’t eat in the library.
Don’t listen to music in the library.
Don’t take pictures/photos in the library.
Let’s go to the 2nd stop!
The 2nd Stop Harry Potter Museum
No eating here!
Don’t eat here!
1’ and a postcard
No climbing here!
Don’t climb here!
3’ and 2 postcards
Let’s go to the 3rd stop!
The 3rd Stop London University
You can not sleep in class.
You can’t sleep in class.
No sleeping in class.
Don’t sleep in class.
No fighting at school.
Don’t fight at school.
祈使句的定义
祈使句是表示请求、命令、叮嘱、号召、劝告等的句子; 通常省略主语you; 句中谓语动词用动词原形; 句尾一般用降调; 祈使句的开头是动词原形。
Close the door, please.
Be careful!
Don't be late for school again!
祈使句的常见结构
1) “Be + 形容词”型
肯定式：Be + 形容词.
否定式：Don’t be + 形容词.
Be quiet, please.
Don’t be late next time.
祈使句的常见结构
2) “行为动词开头”型
肯定式：动词原形+其他.
否定式：Don’t + 动词原形+其他.
Come here, please.
Don’t stand up.
祈使句的常见结构
3) let型
肯定式：Let + 人称代词宾格 +动词原形.
否定式：Let + 人称代词宾格 + not + 动词原形.
Don’t + let + 人称代词宾格 +动词原形.
Let’s go!
Let’s not say anything about it.
Don’t let them make any noise.
祈使句的常见结构
4) “No + 名词或动名词”型
意义：表示“禁止”，含否定含义，经常用于公共场合。
No photos.
No smoking.
易错点1
祈使句中连接词的用法
and用在祈使句后，前后表示顺承，意为“那么”。
or用在祈使句后，前后表示转折，
意为“否则”。
Work harder, and you will be better.
Hurry up, or we’ll be late.
易错点2
祈使句的答语
—Please turn off the light when you go out.
—Ok, I will.
—Don’t be late any more.
—Sorry, I won’t.
由于祈使句所表达的动作都还是未发生的，因此对它的应答通常要用“一般将来时”。
易错点3
祈使句的答语
—Let’s chat on the Internet.
—Good idea.
以let开头的句式的肯定回答多用Good idea! 否定回答用Sorry,…
【典例1】—What are the rules at your school?
—Don’t run in the hallways and ______ arrive late for class.
A. not to B. won’t C. don’t D. no
考查祈使句。句意：—你们学校有什么校规？—不要在走廊里乱跑，不要上课迟到。祈使句的否定形式为Don’t+动词原形+其他.，故选C。
【典例2】______wake up your sister, Ben. She needs a good sleep.
A. Don’t B. Doesn’t C. Aren’t D. Can’t
考查祈使句。句意：不要吵醒你妹妹，本。她需要一个好觉。祈使句的否定形式为Don’t+动词原形+其他.，故选A。
【典例3】—Don’t forget to give my best wishes to your uncle.
—______.
A. No, I don’t B. No, I won’t
C. Yes, I do D. Yes, I would
考查祈使句。句意：—不要忘记把我最好的祝福送给你的叔叔。—是，我不会的。祈使句的回答应根据实际情况来定，且使用一般将来时。
2. 情态动词have?to?的用法
have to意思是“必须、不得不”, 它侧重于客观
上的必要和外界的权威。
1) 结构: 主语＋have?to＋动词原形＋其他.
(一般现在时, 主语是第三人称单数时,
用has?to; 句子是过去时, 用had?to。) 如：
We?have?to?wear?sneakers?for?gym?classes.?
在体育课上, 我们必须穿运动鞋。
Tom?has?to?practice?the?guitar?every?day.?
汤姆每天必须练习弹吉它。
I?had?to?get?up?at?5:00?am?last?Monday.?
上周一, 我不得不早上5点起床。
2) 否定形式: 主语＋don’t?have?to＋动词原形
＋其他.(一般现在时, 主语是第三人称单数时,
用doesn’t?have?to; 句子是过去时, 用didn’t?have?to。)
e.g. Nick?doesn't?have?to?wear?a?uniform.
? 尼克不必穿制服。
We?didn't?have?to?do?our?homework?at?once.?
我们不必马上完成作业。
3) 疑问句: Do (Does 或 Did)＋主语＋have?to?＋
动词原形＋其他?
如: —Do?you?have?to?stay?at?home?on?weekends??
—Yes,?I?do.?/?No,?I?don't.?
——周末你必须待在家里吗？
——是的, 我必须。/ 不, 我不必。
Did?he?have?to?go?to?bed?by?11:00?last?night??
昨晚, 他不得不11点前上床睡觉吗？?
用have to或has to填空。
1.We ________ clean our classroom after school.
2.She _________ make her bed after getting up.
3.It’s late. Mr Beckman ______ go to work by car.
4.Emily and Peter join a music club. They _______ practice the guitar every day.
have to
have to
has to
has to
1) 表示能力, “会”, “能”。例如:
Can?you?play?the?guitar??你会弹吉他吗？
Judy?can?speak?a?little?Chinese.?
朱蒂会说一点中文。
I?can?dance?and?sing.?我能唱歌又能跳舞。
3. 情态动词can的用法
2) 表示允许、许可, “可以”、“能” 。例如:
Can?the?students?run?in?the?hallways??
学生们可以在走廊上跑吗?
We?can?eat?outside.?我们可以在外面吃东西。
Can?I?come?in??我能进来吗?
根据句意，用can和can’t填空。
1. Mr. Green_______ smoke here because there’s a sign on the wall. It says “No smoking.”
2. It’s very hot outside. You______ wear a hat.
3. We _______ eat in the classroom because it’s impolite to teachers.
4. I ______ go to bed after 11:00 on school nights.
5. The students _____ read books and magazines in the library.
can’t
can
can’t
can
can’t
Exercise
Use the words to make questions about the rules. Then write answers according to your school.
Be quiet?
Q: ___________________________________ (she/have to/ in the library)?
A: ___________________________________
Eat?
Q: ___________________________________
(he/have to/in the dining hall)?
A: ___________________________________
Does she have to be quiet in the library?
Yes, she does.
Does he have to eat in the dining hall?
Yes, he does.
Listen to music?
Q: ___________________________________ (we/can/ in the hallways)?
A: ___________________________________
Wear a hat?
Q: ___________________________________
(we/can/in the classroom)?
A: ___________________________________
Can we wear a hat in the classroom?
No, we can’t.
Can we listen to music in the hallways?
No, we can’t.
