必修四第二单元课文二学案

制作人：

王艳辉

审核人

郭光宝

使用时间

4月29日 

年级签字

编号

28

——课前预习案——

1. Why are chemical fertilizers so popular in farming today?

2. What problems can be caused by chemical fertilizers?

3 What is organic farming?

4. What are the methods used by organic farmers?

——课中探究案——

一、检查反馈，导入新课。

二、目标定位，确定重点。

1.掌握文章中的重要短语。

2.掌握文章中的重要语言点。

三、自主探究，教师点拨。

1在过去的半个世纪______________  2.增加产量___________________ 

3. 长期使用化肥                   4.对……造成损害______________

5.洗掉                            6.积累，增强_________________ 

7.导致__________________________  8.除…之外_________________                      

9. 营养丰富______________      10.转向有机农业______________

11.集中精力于______________   12.没有疾病__________________

13.每隔几年______________      14.为…做好准备_______________  

15.阻止…做______________     16.带走______________________   

17.避免______________

四、尝试演练，合作解疑。

1. Recently ,however , scientists have been finding that long-term use of these fertilizers can cause damage to the land and , even more dangerous , to people’s health.

(1)however为副词, 意为”然而，可是 ”，表转折，可用于句首,句末,句中,如在句中,起前后都要加逗号.

例如: He , however ,couldn’t pay for the education that young Albert needed .

(2)however为连词,引导让步状语从句,相当于no matter how ,修饰形容词或副词.

例如:However hot it is , he will never take off his coat .

=No matter how hot it is, he will never take off his coat.

译：                                                       。

However fast you run, you can’t catch up with a car.

=No matter how fast you run, you can’t catch up with a car.

译：                                                  。

2.） have been finding 是现在完成进行时,现在完成进行时的特点是强调”动作的连续性”,但有可能已经终止.

例如:He is very tired , he has been working hard all day .

他很累,他整天都在努力工作.

He has been writing a letter.

译：                                                  。

2. They often change the kind of crop in each field every few years, 他们通常每隔几年就改变一块田地里作物的种类,……

表示”每隔…/每”,表示时间或空间的间隔. 具体用法是 : “every+基数词+复数名词”;”every +序数词+ 单数名词”.

例如:every year 每年

every two years / every second year / every other year每两年(每隔一年)

every three years / every third year /every other two years .每三年(每隔两年)

every four years / every fourth year / every other three years 每四年(每隔三年)

3. Why are chemical fertilizers so popular in farming today?

popular 的用法:

(1)popular 为形容词,意为”受喜爱的，受欢迎的，当红的”. 常用短语:

be popular with sb. 受某人欢迎. 例如:

This is one of our most popular designs.                                                         

Skiing has become very popular recently. __________________________.

I’m not very popular with my parents at the moment. __________________ .

五、当堂检测，拓展延伸。

单项填空

21. — _______ David and Vicky _____ married? — For about three years.

A. How long were; have been B. How long have; have been

C. How long have; been        D. How long did; get

22. Luckily for us, when we got there the weather _______ to be fine.

A. turned up    B. turned out  C. turned over    D. turned into

23. Having heard my answer, the master nodded _______ satisfaction, “I’m quite satisfied _____you.”

A. with; with B. on; by    C. in; to        D. in; of

24. —The matter must be looked into.

— We are supposed to have a little ________ .

A. rain       B. weather.   C. patient      D. look

25. In the traffic accident five were killed and twenty __________.

A. losing     B. missed    C. damaged   D. injured

26. We are _______ happy to hear of the success of their team.

A. enough    B. more than  C. many more  D. much many

27. We won't give up ________ we should fail ten times.

A. even if  B. since      C. whether    D. until

28. —Well, you'd better not buy that shirt. Brown and black don't go together.

— ________ I wear it with my other shirt?

A. How do you like B. Who C. What if   D. Which

29. A middle-aged woman came ________ to the bus stop only ________ the bus had gone.

A. run; to find       B. running; to find

C. and ran; found    D. running; finding

30.___________ your help, I got the first in the final-term English examination.

A. Thanks to              B. Without C. If not                D. But for

31. You should try to get a good night’s sleep __much work you have to do.

A. however    B. no matter   C. although      D. whatever

32. Now that you have a job, you must exert (努力) yourself in ______ you do at work. 

A. however          B. no matter what

C. no matter how     D. whatever

33. She is good ______ playing the piano and good ______ her students, which is good _______ the students.

A. at; for; to    B. to; to; for    C. at; to; for    D. to; at; for

34. She watches TV ____ evening and changes channels(频道) ____ few minutes.

A. in; every   B. every; every  C. every; each  D. every; in

35. _____ is often the case, we have worked out the production plan.

A. Which      B. When       C. What      D. As

六、课堂小结，布置作业。

1.熟记重要短语及语言点。

——课后巩固案——

完成同步练习册练习题。