高中英语同步教案第课时：UnitCloning人教新课标选修_2_1

2014-2015学年高中英语（贵州）同步教案第3--4课时：Unit 2 Cloning 人教新课标选修8）

The third period & fourth period

Speaking and grammar

Step I. Speaking task

“In our earlier class, we learned how to organize a debate, now it’s our turn to continue the debate. The topic of our debate is “should we clone?” Now choose the team you agree with.”

Divide the whole class into four groups, two agree and two disagree.

To begin this debate, I’ll give you some information about clone. You can choose what you need. During the speech, you can make notes so that you do not forget what you want to say. In our debate the person who speaks last must summarize your ideas. Here are some tips for you.

Show the following

Center on the subject

Organize main ideas that support your point of view

List your own idea

Make a conclusion

Show the following

Why should we use cloning?

Notes for debating:

Argument for cloning:

1)Cloning will be beneficial to humans, For example, if a couple can’t have children,

cloning could help give them a child;

2)We could use cloning to cure illnesses.

Arguments against cloning

1)healthy risks form mutation of genes

2)emotional risks

3)against nature

4)risk of abuse of the technology

5)Cloned animals get ill and die quite young;

6)People are afraid of that scientists will create sands of copies of the same person

7)Cloning is dangerous because scientist may create monsters by mistakes.

Step II.

同位语从句和定语从句比较与区分

由于同位语从句的先行词多为fact, belief, news, idea, thought, question, reply, possibility, hope, problem, remark, report等名词,引导词常用that,所以有些同学干脆把这些名词背得滚瓜烂熟,以为只要上述名词后面出现的从句肯定是同位语从句,殊不知上述名词后面出现的从句既有可能是同位语从句,也有可能是定语从句。例如:

(1)We were greatly pleased at the news that the Chinese women's volleyball team had won the match again.听到中国女排再次获胜的消息我们极为高兴。(that引导的是同位语从句)

(2)We were greatly pleased at the news that our teacher had told us.听到老师告诉我们的消息我们感到很高兴。(that引导的是定语从句)

从上面的例句可以看出,仅仅只*先行词就断定有些名词之后一定就是同位语从句显然是片面的。那么,究竟应当如何来区分同位语从句和定语从句呢?一般来说,我们可以从以下几个方面去区分同位语从句和定语从句:

1.从意义的角度来看,同位语从句与先行词之间存在的是同位或等同的关系,如例(1)中的news与其后的从句that the Chinese women's volleyball team had won the match again之间,"中国女排再次获胜"表示"消息"的具体内容。定语从句与先行词之间存在的是所属关系,表示"……的",起修饰限定作用。如例(2)中的news与其后的that our teacher had told us"老师告诉我们的"是对"消息"进行修饰限定,并不表示"消息"的具体内容。

2.从语法角度来看,引导同位语从句的that是连词,只起语法作用,用来连接同位语从句,在从句中不充当任何成分,如例(1)中的that;而引导定语从句的that是关系代词,它除了起引导从句的语法作用之外,还要在从句中充当句子成分,主要是作主语或宾语,如例(2)中的that在从句中作动词told的宾语。

3.从先行词的词性来看,同位语从句的先行词大都为抽象名词,而定语从句的先行词可以是名词,也可以是代词。例如:

(1)There is no doubt that the price of wheat will go up.毫无疑问,小麦的价格将会上涨。(doubt为抽象名词,同位语从句)

(2)Those who were against the plan raised their hands.那些反对这个计划的人举起了手。(Those为代词,定语从句)

4.从可否省略来看,同位语从句的that一般不可以省略,但是定语从句中的关系代词如果在从句中充当宾语,在非正式用语中常常可以将关系代词that省略。

5.从引导词来看,同位语从句有时也可以用whether来引导,但是定语从句则一般不用whether来引导。例如: