人教新课标高中英语选修六Unit4Grammar教案

人教选修6 Unit4 Global Warming

Grammar

Teaching material

NSEFC Book 6 —— Unit 4

Teaching aims

Enable the students to master the usage of the form it is/was... that.....

Teaching important points

How to enable the students to know the structure and the usage of the form it is/was... that.... Teaching difficult points

How to help the students to master the usage of the form it is/was... that....

Teaching aids

tape recorder, slides

Teaching procedures

Step1 Revision

T: First let’s check answers. (slide show)

Discovering useful words and expressions. (P28)

1. Charles Keeling collected ______on the carbon dioxide content in the atmosphere over a forty-year period. He found that the amount of carbon dioxide _______ increa sing during that time.

2. Although we are burning coal in huge _________ every year, we won't ______ __ of it for centuries.

3. If the amount of greenhouse gases continues to _______ we could be facing a gl obal __________.

4. Many scientists believe that global warming has __________ through the burning of fossil fuels. They do not think that ignoring the issue is worth the ____.

5. ______ describes weather conditions over a period of years in a particular place.

6. The _____________ of a rising sea level would be widespread flooding.

7. The use of energy in Susanna's country is low ______________ the use of energy in the USA.

8. The warming of the earth is a _____________ that causes great concern.

9. The ________ shows temperature changes during the 20th century.

10. One hectare of forest can absorb 23 tons of carbon dioxide ____ year.

Keys：1.data kept on 2. quantities; run out 3. build up; catastrophe

4. come about; risk

5. Climate

6. consequence

pared to

8.phenomenon

9. graph 10. per

Answer keys for Ex.2 on Page 28:

The first graph shows the global _______________ between ________ and ________

_The temperature __________ and decreased over this period but on the whole it __ _______ by around _________ and its highest in 2000. There was a steady _______ __________ in the temperature during the twenty years after 1980. We can see from the graph that the earth has become ___________ since early last century.

The second graph shows the amount of ______________in the atmosphere from ____ ____ to _______ .The carbon dioxide __________ steadily over this forty-year period. It went up from 315 to 370 parts ___________million.

Keys：

Temperature；1860；2000；increased；rose；1910；increase/rise；warmer

carbon dioxide；1957；1997；increase/ went up；per

Step2 Grammar

强调句结构

常考的强调句结构是it 引导的句子。

一、It is (was) 被强调部分+ that (who) + 句子其他部分。此结构强调的成分仅限于主语，宾语和状语。

It is from the sun that we get light and heat.

It was not until I had read your letter that I understood the true state of affairs.

Karl bought Marva a bicycle on her birthday．卡尔在玛瓦生日那天给她买了一辆自行车。

It was Karl that／who bought Marva a bicycle on her birthday．（强调主语）

It was Marva for whom Karl bought a bicycle on her birthday．（强调间接宾语）

It was a bicycle that Karl bought Marva on her birthday．（强调直接宾语）

注意区别强调句中的that／who分句与定语从句：

It was the student that／who asked the silly question．是一个学生问了这么一个愚蠢的问题。（分裂句）

He was the student who asked the silly question．他就是问了这么一个愚蠢问题的学生。（划线部分是定语从句）

二、not ... until ... 的强调形式: It is not until + 被强调部分+ that ... “直到…才…”，主要用于强调时间状语的强调句型。

We did not begin studying French until we entered university．我们进了大学才开始学法语。要强调until we entered university，就成了：

It was not until we entered university that we began studying French．

______ the 18th century that man realized that the whole of the brain was involved in the wo rkings of the mind．

A. During

B. In

C. It was until

D. It was not until

D对。直到十八世纪，人们才意识到：心理活动与整个大脑有关。

三、强调句的疑问句句型

1.强调句的一般疑问句句型:

Is / Was +it +所强调的部分+that / who/ whom +其它?

2.强调句的特殊疑问句句型:

特殊疑问词+ is/was it that / who/ whom+其它?

Why is it that you hate winter？你究竟为什么不喜欢冬天？

How was it that you missed such a wonderful lecture？你怎么会错过这么精彩的报告？When was it that they went abroad？他们什么时候出国的？

四、判断强调句的方法

判断是否是强调句是，可把It is / was …that 去掉，剩余部分在不增减任何词的情况