名詞性從句復(fù)習it作形式主語演示教學

1、名詞性從句復(fù)習it作形式主語Learning goals learn that the preparatory subject/empty subject it is often used to balance the sentence with a long subject. The empty subject it acts as its grammatical subject and the real subject is at the end of the sentence.when we use a noun clause as the subject of a sentence.當

2、句子的主語是從句時，我們一般用當句子的主語是從句時，我們一般用it作形式主語。作形式主語。 a. (correct) That languages borrow words as they are developing is inevitable.= (preferable) It is inevitable that languages borrow words as they are developing. b. (correct) Whether “borrowed words” are good or bad remains a question.= (preferable) It r

3、emains a question whether “borrowed words” are good or bad.1. We can use it as an preparatory subject.Preparatory subject “it”: 1.That we would be not able to understand Old English today is certain. = It is certain that we would not be able to understand Old English today. 2.Whether English will co

4、ntinue changing in the future is easy to answer. = It is easy to answer whether English will continue changing in the future. 3.When we can set off depends on the weather.= It depends on the weather when can we set off. (correct) To master a foreign language is hard. (preferable) It is hard to maste

5、r a foreign language. b. (correct) To gain access to the Internet is important for us. (preferable) It is important for us to gain access to the Internet.B. when the subject is a to-infinitive.當句子的主語是不定式時，我們一般用當句子的主語是不定式時，我們一般用it作形式主語。作形式主語。C. when the subject is a v-ing form.當句子的主語是動名詞當句子的主語是動名詞v-i

6、ng時，我們一般用時，我們一般用it作形式主語。作形式主語。a. (correct) It is difficult to stop smoking. = ( preferable) Smoking is difficult to stop. b. (correct) It takes a lot of my time travelling to Beijing. = (preferable) Travelling to Beijing takes up a lot of my time. We usually use the preparatory subject it with a cla

7、use or to-infinitive (preferable), but with the v-ing form we prefer the real subject at the beginning. 通常情況下，當句子的主語是從句或動詞不定式時，通常情況下，當句子的主語是從句或動詞不定式時，我們一般用我們一般用it作形式主語。作形式主語。當句子主語是動詞的當句子主語是動詞的-ing形式時，我們則一般將真正的主語置于句首，而不使形式時，我們則一般將真正的主語置于句首，而不使用用it作形式主語。作形式主語。Tip2. 當當seem, appear, happen, turn out 和和p

8、rove 在句在句子中作謂語動詞時，我們也可以使用形式主語子中作謂語動詞時，我們也可以使用形式主語it。 It seems that he speaks two languages. = He seems to speak two languages.b. My new neighbor happens to come from my home town. = It happens that my new neighbor comes from my home town. 3. 在在It is known .; It is said .; It is hoped .; It is believ

9、ed .等句型中。如等句型中。如: It is said that our school football team won. 主語從句也可以用主語從句也可以用it作形式主語作形式主語,以以wh-連接的連接的句子作真實主語句子作真實主語, 放到句子后面放到句子后面.如如:It is still a question when we shall have our sports meet.It doesnt matter what you say.4. It is / was + 被強調(diào)部分被強調(diào)部分 + that / who . 該句型是強調(diào)句型。被強調(diào)部分可以是主語、該句型是強調(diào)句型。被強調(diào)部

10、分可以是主語、賓語、表語或狀語。強調(diào)的主語如果是人，賓語、表語或狀語。強調(diào)的主語如果是人，that 可以由可以由 who 換用。如果把這種句型結(jié)構(gòu)換用。如果把這種句型結(jié)構(gòu)劃掉后，應(yīng)該是一個完整無缺的句子。這也劃掉后，應(yīng)該是一個完整無缺的句子。這也是判斷強調(diào)句型與其它從句的方法。是判斷強調(diào)句型與其它從句的方法。 It is on Tuesday that she will come.Finish exercises A &B, page 31The key to Exercise A(2) It requires a good understanding of their behavio

11、r to know what they mean.(3) It always puzzles me why my dog barks in certain ways.(4) It wont be difficult to buy a machine like this.The key to Exercise B2. It happens that several racial groups live in Singapore.3. It is fun to hear different people speaking different languages all at the same ti

12、me.4. It is certain that Ill see you next week.高考鏈接高考鏈接1. It was never clear _ the man hadnt reported the accident sooner. (2011江蘇江蘇) A. that B. how C. whenD. whyD2. Im afraid hes more of a talker than a doer, which is _ he never finishes anything. (2011山東山東) A. that B. when C. where D. whyD3. Befor

13、e a problem can be solved, it must be obvious _ the problem itself is. (2011湖南湖南) A. what B. that C. which D. whyA4.（2012上海卷）上海卷）Weve only got this small bookcase. Will that do?No, _ I am looking for is something much bigger and stronger.who B. that C. what D. whichC5.（2012全國卷）全國卷）It is by no means clear _ the president can do to end the strike. A. how B. which C. that D. whatD6. (2013湖南湖南) Do not let any failures discourage you, for you can never te