1、Although the four countries do work together in some areas，they are still very different.?
although 引導讓步狀語從句：雖然這四個國家確實在某些領域合作，但它們仍然非常不同。
2、as if / though 引導的狀語從句，時常用虛擬語氣，表示與事實不符或相反的情況
He spoke in that way as if he were a foreigner. 他講話的方式就好像是老外。
3、as + adj. + a + 可數單數名詞 + as … ：as---as 像---一樣：第一個as是副詞，修飾形容詞或副詞的'原級;
第二個as是連詞，引導比較狀語從句。在否定句中也可以改為not as(so)---as-----.
The film was not as/so good as I had expected. 這部電影不如我預期的好。
4、be about to do sth…when… 正要幹……這時…… when == at that time
I was about to leave when the manager called me back. 我正要離開時,經理叫住了他。
5、believe it or not 信不信由你，用於口語中，相當於插入語
Believe it or not, he asked me to tell you a lie! 信不信由你，他要我向你說謊!
6、can / could have done 表示對過去發生的行為進行推測，“可能”。一般用於否定句和疑問句
He can’t / couldn’t have done it because he was an honest man.
(1)must have done常用於肯定句，“一定” It must have been very late when he left the office.
(2)may / might have done 可能、也許，用於否定和肯定句中 He may / might have heard it from Mary.
(3)should have done表示“本該做某事，而結果未做”，否定句表示“不該做某事而結果做了”
He should not have taken the old clothes away. 他不該把舊衣服帶走。(事實上已帶走啦)
(4)needn’t have done 本來不需要---，但是做了… He needn’t have done his homework yesterday.
7、even if / though--- -即使、雖然
Even if we can go out for play, we won’t do. 即使我們能出去玩，我們也不想去。
8、Exhausted, I slid into bed and fell fast asleep. 由於太累了，我倒在床上馬上就睡著了。
exhausted表原因，相當於一個原因狀語從句As I was exhausted
9、Finding that Zhinu was heart-broken , her mother finally decided to let the couple cross the Milky Way to meet once a year.
Finding that Zhinu was heart-broken 是現在分詞短語作原因狀語，表主動動作。主句的主語與v.-ing有邏輯上的主謂關係
10、He couldn’t have Yong Hui getting away with telling people lies! 他不能讓永慧跟別人說謊而置之不理。
(1)have sb. doing sth. 讓某人做某事，表示一個持續的動作。放在否定句中表示不允許某人幹某事。
(2)have sb. do sth. 讓某人做某事(省略to的不定式)，指做一次性的具體動作;
I’d have you know that I am ill. 我要讓你知道我病了。
11、He got interested in two theories explaining how cholera killed people.?
他對兩個關於霍亂為什麼能致人於死地的理論感興趣。
how 引導的特殊疑問句是賓語從句
12、 However + adj. / adv. + 主語 + 謂語
however = no matter how無論如何，不管怎樣，引導讓步狀語從句
However/No matter how cold it is, he always goes swimming.
13、主語 + be + adj.+ to do Tom is pleasant to work with. 與湯姆共事很令人愉快。
14、If so so用if 之後，代替前面的分句或句子，構成縮略條件句，語義可由上下文語境得知。
Will you get a free evening next week? If so, let us have dinner.
15、in search of 尋找，尋求
I’m always in search of someone who has the same hobby with me.
16、It is time -----
(1)It is time to do sth. 到了---的時間啦。
(2)It’s time (for sb.)to do sth. 到了某人幹----的時間啦。 It’s time for us to have a lesson.
(3)It’s (high/about) time that 從句到了某人幹----的時間啦
(4)It /That/This/was/is the first/second----time that---- 這是某人第一、第二---次做某事 It’s the first time that I have been here.
17、It is too bad you can’t go as far as Ottawa. as far as 有三層基本的意思
(1)到某一指定的地點;遠達 He walked as far as the park. 他步行到花園。
(2)同樣的距離 We didn’t go as far as others. 我們不如別人走的遠。
(3)程度、範圍。就----而言，至於。也可以寫做 so far as
As / So far as I know, he isn’t coming to the party. 據我所知，他不會出席這個晚會了。
18、It / This / That is the + 序數詞 + time that 這是某人第一次/第二次/第三次做某事。
該結構中，that引導的從句為定語從句，通常用完成時態。time亦可為其它名詞所替代
This is the first time (that) I’ve felt really relaxed for months. 幾個月來這是頭一次我真的感到輕鬆了。
It was the third time that he has fallen in love that year. 這是他那一年第三次談戀愛了。
19、It looked splendid when first built. 剛建起來的時候很輝煌。?
(1)本句是一個複合句，when引導時間狀語從句;
(2)When first built是When it was first built的省略
Be careful when(you are)crossing the street.?過街時要當心。?
20、It was obvious that the manager of the coffee shop was waiting for Li Fang to leave…
句子中it作形式主語，其後的從句才是句子的真正主語。
(1)It’s a pity (a shame a fact a wonder...) that...
It’s no harm drinking running water in that area.在那個地區喝自來水是無害的。
(2)It is strange (obvious true good possible likely clear...) that...
It is easier to say than to do.說比做容易。
(3)It seems (happened turned out occurred to me) that...
It seems that it is going to rain a moment later.
(4)It is said (reported decided expected...) that.
It is said that the tickets have been sold out.據說票已售完。
