Unit 4 Don’t eat in class Section A Grammar Focus-3c 课件(共36张PPT)+内嵌视频

(共36张PPT)
Unit 4 Don’t eat in class.
Section A Grammar Focus-3c
Learning objectives
1. Functions: talk about rules
2. Grammar: ① 祈使句(重点为否定结构)
② 情态动词can表“许可”的用法(肯定及否定陈述，
一般疑问句结构及肯定和否定回答)
③ 情态动词must的句型结构(仅限肯定陈述)
④ 情态动词have to的句型结构(肯定及否定陈述，一般
疑问结构及肯定和否定回答)
Presentation
How to talk about rules
Grammar Focus
Don’t run in the hallways. Don’t fight.
What are the rules We must be on time for class.
Can we eat in the classroom No, we can’t, but we can eat in
the dining hall.
Can we wear a hat in class Yes, we can./No, we can’t.
Does he have to wear a uniform at school Yes, he does./No, he doesn’t.
What do you have to do We have to be quiet in the library.
Observe this chart.
Grammar Focus
祈使句的否定句怎样构成？肯定句呢？一般在什么情况下会用祈使句？
情态动词在用法上有什么共同点？
can在本单元主要表示什么含义？它还可表达什么意思？
have to在句法上与其他情态动词有何区别？
Work in pairs and answer the questions.
课堂检测
Don’t run in the hallways. Don’t fight.
What are the rules We must be on time for class.
Can we eat in the classroom No, we can’t, but we can eat in
the dining hall.
Can we wear a hat in class Yes, we can./No, we can’t.
Does he have to wear a uniform at school Yes, he does./No, he doesn’t.
What do you have to do We have to be quiet in the library.
Grammar Focus
祈使句的否定句怎样构成？肯定句呢？
祈使句的否定句在动词原形前加don’t，表示“不要做什么事”。
祈使句的肯定句通常是以动词原形开头的。
Don’t run in the hallways. Don’t fight.
What are the rules We must be on time for class.
Can we eat in the classroom No, we can’t, but we can eat in
the dining hall.
Can we wear a hat in class Yes, we can./No, we can’t.
Does he have to wear a uniform at school Yes, he does./No, he doesn’t.
What do you have to do We have to be quiet in the library.
Grammar Focus
一般在什么情况下会用祈使句？
祈使句一般用于上级对下级，长辈对晚辈之间，表示命令、劝说或警告，也可表示请求。
Don’t run in the hallways. Don’t fight.
What are the rules We must be on time for class.
Can we eat in the classroom No, we can’t, but we can eat in
the dining hall.
Can we wear a hat in class Yes, we can./No, we can’t.
Does he have to wear a uniform at school Yes, he does./No, he doesn’t.
What do you have to do We have to be quiet in the library.
Grammar Focus
情态动词在用法上有什么共同点？
can, must, have to后接动词原形。
Don’t run in the hallways. Don’t fight.
What are the rules We must be on time for class.
Can we eat in the classroom No, we can’t, but we can eat in
the dining hall.
Can we wear a hat in class Yes, we can./No, we can’t.
Does he have to wear a uniform at school Yes, he does./No, he doesn’t.
What do you have to do We have to be quiet in the library.
Grammar Focus
can在本单元主要表示什么含义？它还可表达什么意思？
can的意思是“能够；允许“，还可表示“能力” 。
Don’t run in the hallways. Don’t fight.
What are the rules We must be on time for class.
Can we eat in the classroom No, we can’t, but we can eat in
the dining hall.
Can we wear a hat in class Yes, we can./No, we can’t.
Does he have to wear a uniform at school Yes, he does./No, he doesn’t.
What do you have to do We have to be quiet in the library.
Grammar Focus
have to在句法上与其他情态动词有何区别？
have to有人称和数的变化。
Grammar Focus
祈使句一般用来表示请求、命令、劝说、号召、警告等。在祈使句中，通常省略主语you，其肯定形式以动词原形开头，否定形式是在动词原形前加don’t。祈使句句尾用句号或感叹号，读时用降调。为表示礼貌，可以在句首或句尾加上please。句末用please时，前面通常加逗号。
语法概述
祈使句助“抗疫”
肯定句：动词原形 (+宾语)+其他.
否定句：Don’t+动词原形 (+宾语) +其他.
Wear mask!戴口罩
Stay home and work out!在家做运动。
Don’t go to the places where there are lots of people. 不要去人多的地方。
Do 型祈使句的构成
Presentation
Presentation
肯定句：Be+表语+其他.
否定句：Don’t+be+表语 +其他.
Be careful .要细心。
Don’t be nervous! 不要紧张。
Be 型祈使句的构成
Presentation
肯定句：Let+宾语+动词原形+其他.
否定句：Don’t+let+宾语+动词原形+其他.
或Let+宾语+not+动词原形+其他.
Let’s all say goodbye to virus. 一起和病毒说bye-bye。
Don’t let the virus get in. = Let virus not get in. 不要让病毒钻进来。
Let 型祈使句的构成
Presentation
其他类型的否定祈使句
(1) No+v-ing! / No+名词!
No fishing! 禁止钓鱼!
No parking! 禁止停车!
No photos! 禁止拍照!
(2) never 代替don’t 来加强语气。
Never give up! 决不放弃!
Grammar Focus
情态动词have to与must
We must be on time. 我们必须准时。
Does he have to wear a uniform at school 他在学校必须穿校服吗？
He has to live at school because his home is far away from school. 他不得不住校，因为他家离学校很远。
语法示例
Presentation
二者均可表示“必须”，其后均接动词原形。
It’s too late. I have to take a taxi. 太晚了，我必须乘出租车。
I must go now. 我必须现在就走。
have to与must的共同点
Presentation
have to与must的不同点
have to 强调因客观因素影响而不得不做某事，跟主观意愿无关，通常上下文中会有暗示客观因素的句子，多译为“不得不”。
must 表示因主观需要或责任感的驱使而有必要或义务去做某事，多译为“必须”。
Presentation
have to与must的不同点
have to 可用于不同的时态，有人称和数的变化，其一般现在时的第三人称单数形式为has to；过去式为had to。
must 一般只用来表示现在，没有人称和数的变化。
Presentation
have to与must的不同点
have to have to的否定形式为don’t/doesn’t /
didn’t have to，表示“不必”。
must must的否定形式为mustn’t，表示“禁止，不准“。
Presentation
He has to leave school because his family is poor. 因为家里穷，他不得不退学。(受客观因素影响)
We must do something about it. 关于这件事我们必须做点什么。(责任感的驱使)
【拓展延伸】以must开头的一般疑问句的肯定回答用must，否定回答用needn’t或don’t have to。
—Must I leave now 我现在必须离开吗？
—Yes, you must./No, you needn’t (don’t have to). 是的，你必须。/不，你不必。
Presentation
Write the rules for the school library.
3a
Library Rules
1. ____________________________
2. ____________________________
3. ____________________________
4. ____________________________
Don’t talk.
1
2
3
4
Don’t eat in the library.
Don’t listen to music in the library.
Don’t take photos in the library.
Presentation
Use the words to make questions about the rules. Then write answers according to your school.
Q: Does she have to be quiet in the library (she/have to/in the library)
A: Yes, she does.
Be quiet
3b
Q:Does he have to eat in the dinning hall (he/ have/in the library)
A:Yes, he does.
Eat
Q:_________________________________(we/can/in the hallways)
A:_________________________________
Presentation
Listen to music
Can we listen to music in the hallways
No, we can’t.
Wear a hat
Q:_________________________________(we/can/in the classroom)
A:_________________________________
Can we wear a hat in the classroom
No, we can’t.
Presentation
the students/have to/clean classroom/every day
she/have to/be at home/at five o’clock
she/have to/do morning reading/every day
we/can/arrive at school/late
Make more conversations using these words.
Presentation
Make up five cool rules for your dream school. Share your rules with the class. Your classmates vote for the Coolest School!
3c
1.We can eat in class.
2.We don’t have to come to school every day.
3. ...
At my dream
school, we don’t have
to come to school
every day. We...
延伸拓展
Exercises
一、单项选择
1
2
3
David, _______ make trouble at school.
can’t B. don’t C. doesn’t
—Mom, can I play computer games this evening
—_______ your homework first, and then we’ll talk about it.
A. Finishing B. Finish C. To finish D. Finished
Buses _______ stop when the traffic lights turn red.
A. can B. may C. must
B
B
C
Exercises
二、句型转换（每空一词）
Talk in class. (改为否定句)
______ ______ in class.
I have to do my homework after school. (对画线部分提问)
______ ______ you ______ ______ ______ after school
We have to listen to the teacher. (改为一般疑问句并作肯定回答)
______ we ______ ______ listen to the teacher
______, we ______.
Don’t
talk
Do
have to
What
do
have to do
Yes
1
2
3
do
She has to wear the uniform at school. (改为一般疑问句，并作肯定回答)
_____ she _____ to wear the uniform at school
_____, she _____.
We can run in the hallways. (改为否定句)
We _____ run in the hallways.
4
5
Yes does
Does have
can’t
Exercises
Summary
Unit 4 Don’t eat in class. (Grammar Focus-3c)
祈使句(重点为否定结构)
情态动词can表“许可”的用法(肯定及否定陈述，一般疑问句结构及肯定和否定回答)
Grammar
情态动词must的句型结构(仅限肯定陈述)
情态动词have to的句型结构(肯定及否定陈述，一般疑问结构及肯定和否定回答)
Homework
学校组建了一个音乐俱乐部，现在向全体同学征求俱乐部规则，请写出你的合理建议，至少五条。