必修3英語第四單元第三課時導學案
第三課時 grammerlearning aims:
to learn the noun clauses as the subject.
to master the grammer.
課前預習
look at the following sentences, paying attention to the underlined part.
1.after that, what happened to the amber room remains a mystery.
2. it was obvious that the manager of the coffee shop was waiting for li fang to
leave …
課堂學習
task 1:discussion
sentences from this unit
1.… it was not clear whether the shape would last or not.
2. what is even more important is that as the earth cooled down, water began to appear on its surface.
3. it was not immediately obvious that water was to be fundamental to the development of life.
4.so whether life will continue on the earth for millions of years to come will depend on whether this problem can be solved.
5. how life began on earth is one of the biggest puzzles that scientists found hard to solve
discuss the use of whether , what, that, how
task 2語法解讀
主語從句
在復合句中充當主語的句子叫主語從句。主語從句主要由that,和wh-詞引導。
1.that引導的主語從句
要點提示:
（1）that引導的主語從句既可以放在句首，也可以放在句后。但為了保持句子的平衡，常用it作形式主語，把真正的主語放在句子的后面。
（2）用it作形式主語的that從句有的已形成固定用法和譯法。常見的如下句型:it +be+形容詞（過去分詞、名詞、不及物動詞等）+that從句。
典型例句:
that he survived the accident is a miracle.=it is a miracle that he survived the accident.
他在這場事故中幸免于難，真是奇跡。
it is natural that she should cry.她大哭是人之常情。
it is a great pity that you can’t help us.你不能幫助我們真是非常的遺憾。
2.wh-引導的主語從句
要點提示:
(1)wh-引導的主語從句既可以直接放在主語的位置，也可以用it作形式主語。
(2)在wh-引導的主語從句中不能用it作形式主語。這里指的是what，whatever，whoever等引導的主語從句通常不能用it作形式主語
（3）在wh-引導的主語從句只能用it作形式主語的情況:如果主語從句是一個疑問句，要用it作形式主語。在“it doesn’t matter +how/whether +if...”結構中要用it作形式主語。
典型例句:
what is most important in life isn’t money.
人生最重要的并不是金錢。（作主語）
how he escaped still puzzles us.
他究竟是如何逃脫的至今仍然令我們百思不得其解。（how引導主語從句，并在句中作方式狀語）
who was responsible for the accident is not yet clear.
還不清楚誰對此事負責任。（作主語）
when he will come has not been clear.
他何時來還不清楚。（when引導主語從句，并在句中作時間狀語）
whether she comes or not doesn’t concern me.
她來不來不關我的事。（這里whether不能if用替換）
whoever wants to see the film may get a ticket free.