(
课件网) Unit 4 Unit 4 Breaking boundaries It as an empty subject To learn the usage of it as an empty subject To learn to describe a city by using it as an empty subject I dropped my watch and it broke. 2. There is a knock on the door. It must be the postman. 3. What’s this It’s a new machine. something somebody pronoun What have we learnt about it 4. It is Friday today. 5. It was very cold last Monday. 6. It lies in the south of Anhui. 7. It is about 8:30 now. 8. It is about 25km from my city to the capital. 9. It is 39 degree! You got a high fever! date weather place time distance temperature a But it is vital not to take any chances. b But not to take any chances is vital. _____ c It is important to remember that Ebola doesn’t respect national boundaries. d To remember that Ebola doesn’t respect national boundaries is important. Look at the sentences and answer the questions. Sentences (a) and (c) are from the reading passage. 1 a But it is vital not to take any chances. c It is important to remember that Ebola doesn’t respect national boundaries. 1. What does “it” refer to in sentences (a) and (c) “It” refers to “not to take any chances” in sentences (a) and “to remember that Ebola doesn’t respect national boundaries” in sentence (c). 2. What is the difference between the sentences in each group Why does the author choose to use sentences (a) and (c) instead of (b) and (d) The first sentences in each group use “it” as an empty subject at the beginning of the sentences. The reason why sentences (a) and (c) are chosen is that the sentences are kept balanced and the key information of the sentences is emphasised. I felt it was my duty as a doctor to go there and offer my help. It is so inspiring to have colleagues like Wilton, Maisy and Alfonso. … it is absolutely essential for us all to collaborate to create a global community with a shared future of peace and prosperity. Now look for more sentences with this structure in the reading passage, and summarise its use in your own words. it作形式主语，常代替由不定式(短语)、动词-ing形式(短语)或从句等真正主语，并将真正的主语后置。 it作形式主语，所代替的是句子的逻辑主语，并无实际词义。 it作形式主语，以保持句子的结构平衡，避免主语过长，显得头重脚轻。 it作形式主语 it作形式主语的作用主要分三种情况 1. be+形容词+不定式(短语) (It is + adj. + to do sth.) e.g. It is difficult to translate the book. 2. be+名词+不定式(短语) (It is + n. + to do sth.) e.g. It was her duty to clean the room. 3. be+介词短语+不定式(短语) e.g. It was against my principle to do that. 4. 及物动词+宾语+不定式(短语) e.g. It cost 150 yuan to buy the dress. 一是代表不定式(短语)，根据句子的谓语又可分为四种类型： It’s no use / good / fun doing sth. It’s a waste of time doing sth. 做某事没有用 / 没有好处 / 没有意思 / 是浪费时间 e.g. It is no use complaining. It’s pleasant sitting here. 二是代表动词-ing形式 一般以“be+名词”作谓语 也可以以“be+形容词”作谓语 1. It + be ... ...
