In transformed structures 2. It is +n +that 从句 What a pity it is that you didn't come to this party. 当名词为a pity/a shame /a surprise +should +v原形 （表示竟然） What a pity that she should be fail in exam. It is of no/little importance whether/if it will rain today.
2. Pron as subject Who is speaking, please? That's OK.
In transformed structure It was at ten that I got home.强调句 It is +adj. +of sb.(人的属性）/for sb.（物的属性）to do It is necessary to finish the design before National day. it is +n.+for/of sb. to do It is not good manners for Arabs to stand close talking to their friends. 在感叹句中：What a joy/ pleasure (it is) to read the book. 在问句中：Is it possible to go to the moon by spaceship?
That they will go is certain. Whether she will come or not is still a question. Whether she's coming or not doesn't matter too much. Who made the long distance call is not important. Whoever leaves the room last ought to turn off the lights. What he said at the meeting astonished everybody present. Why he didn't come here is not clear to anyone. How a telephone works is a question which not everyone c an answer. Where she has gone is not known yet. When they will start has not been decided yet.
3. Num. as subject Two will be enough. Two-thirds of the workers are women. Ten out of 100 Americans are over /above /more than 65.
4. –ing as subject Skating is good exercise. Lookinhe dictionary took him a lot of time.
6. Nominalized phrase the+adj the +p.p prep.p, 疑+to do
The blind and the lame are well cared for in our country. The unemployed usually lead a hard life. From my home to school is three kilometers. Early to bed and early to rise makes a man healthy. When to leave is not decided. How to do well is an important question.
8. Clause as subject 主语从句 What has happened proves that our policy is right.
Whether we'll go depends on the weather.
主语从句的引导词：
that （不省略） whether（不用if）
It is not good manners for Arabs to stand close talking to their friends. 在感叹句中：What a joy/ pleasure (it is) to read the book. 在问句中：Is it possible to go to the moon by spaceship?
In transformed structures 1. It +be+adj+that 从句 It is strange that he didn't come here yesterday. 当形容词为important necessary strange /that should + 动词原形 It is strange that he should （表示吃惊）pass the exam.
In aspect and voice 主动: doing一般/having done完成 被动：being done一般/having been done完成 否定：not doing一般/not having done完成
一般式：无时间限定/与谓语同时出现/在谓语动词后发生
完成式：发生在谓语之前 In transformed structures it 作形式主语：It is no use/good----There’s no doing ---It ’s no use crying for the spilled milk. There’s no getting along with her.
Subject
Subject 主语: 句子说明的人或事物。 The sun rises in the east. (N.) He likes dancing. (Pron.) Twenty years is a short time in history. (Num.) Seeing is believing. (Gerund) To see is to believe. (Infinitive) What he needs is a book. (subject clause) It is very clear that the elephant is round and tall like a tree. (It-grammatical subject)
passive
(not) to be done
(not) to have been done
一般式： 动作发生在谓语之后，或几乎同时发生
进行式：表示与谓语动词同时发生 完成式：发生在谓语动词之前动作 完成进行式：从过去开始一直持续到谓语动词这个动作的发生
In transformed structures It is +adj./n. +for sb.+ to do It is important for you to help me.
5. To do… as subject （不定式表示一种确定的动作）
To translate this ideal into reality needs hard work.
In aspect and voice
simple Active (not) to do progressive perfective Perfective progressive (not) to have been doing (not) to be doing (not) to have done
In transformed structures
4. It +动词原形seem/appear /turn out/+that It seems that it will rain. 5. It strikes sb. that 从句 ，某人突然想 It occurs to sb. that----It occurs to me that I left my key in the classroom. 6. It doesn't matter whether ---It doesn't matter whether it is new/it will rain tomorrow.
1. Noun as subject David arrived last night.
Pride goes before a fall.
In transformed structure The villagers didn't realize how serious the pollution was until the fish in the river died. 倒装：Not until the fish in the river died did the villagers realize how serious the pollution was. 强调：It was not until the fish died in the river that the villagers realized how serious the pollution was.
3. It is +过去分词+that 从句 It is reported that a car accident happened there. He is said to be studying in the USA. 有人建议suggest/order/request + 从句 should +动词 原形