1、not...until... 直到......才......

考點(diǎn) till和until既可以做介詞，加名詞構(gòu)成介詞短語(yǔ)，也可以作從屬連詞引導(dǎo)時(shí)間狀語(yǔ)從句，用于肯定句或否定句中。

till now/until now 迄今，到現(xiàn)在為止

till/until then 直到那時(shí)

till/until the end 直到最后

例句 You want to see a very interesting film with your friend,but your friend can't go until he/she finishes cleaning his/her bicycle.

你想和朋友去看一部有趣的電影，但是你的朋友要等到擦完他的自行車才能去。

若“not until +時(shí)間”狀語(yǔ)位于句首，則主句用部分倒轉(zhuǎn)

例句 Not until that moment did I realize its depth.

直到那時(shí)我才意識(shí)到它的深刻。

2、while doing... 當(dāng)......時(shí)候

考點(diǎn) 在主從復(fù)合句中，當(dāng)從句中的主語(yǔ)與主句中的主語(yǔ)一致時(shí)，而且謂語(yǔ)中含be的某種形式時(shí)，可將從句中的主語(yǔ)和be省略。

例句 While walking the dog,you were careless and it got loose and was hit by a car.

在遛狗時(shí)，你粗心讓狗跑了，結(jié)果它被車撞了。

If asked to look after luggage for someone else,inform the police at once

如果有人要求你幫忙照看行李，請(qǐng)立即報(bào)警。

3、It is/was because +從句 那是因?yàn)?.....

because引導(dǎo)的是表語(yǔ)從句，其后接原因，在It is之后只能用because來(lái)引導(dǎo)表示原因的表語(yǔ)從句，不能用since或as。

I wonder if it's because I haven't been able to be outdoors for so long that I've grown so crazy about everything to do with nature.

我不知道這是不是因?yàn)槲议L(zhǎng)久無(wú)法出門的緣故，我變得對(duì)一切與大自然有關(guān)的事物都無(wú)比狂熱。

4、There was a time when... 曾經(jīng)有一段時(shí)間......

考點(diǎn) 句型中when引導(dǎo)的是定語(yǔ)從句，修飾先行詞a time。a time指的是用一段時(shí)間，還可以用times。

例句 I can well rememner that there was a time when a deep blue sky,the song of birds,moonlight and flowers could never have kept me spellbound.

我記得很清楚，曾經(jīng)有一段時(shí)間，湛藍(lán)的天空、鳥兒的歌唱、月光和鮮花，從未令我心迷神往過。

5、stay+形容詞 保持......

考點(diǎn) “stay+形容詞”構(gòu)成系表結(jié)構(gòu)，stay后可接形容詞作表語(yǔ)，也可接名詞作表語(yǔ)。（同樣的詞還有continue,keep,remain,lie,stand）

例句 For those with family members far away, the personal computer and the phone are important in staying_____.

A. connected B. connecting C. to connect D.to be connected

6、It is/was the first time that sb. have/had done sth.

這是某人第一次做某事。

考點(diǎn) 在此句型中，主語(yǔ)除it以外還可以是this，that等，其中的time也可以用day,year,month等時(shí)間名詞代替，從句中的that可省略。但是，從句中的謂語(yǔ)動(dòng)詞必須用完成時(shí)態(tài)。如果謂語(yǔ)動(dòng)詞是is，則用現(xiàn)在完成時(shí)；如果謂語(yǔ)動(dòng)詞是was，則用過去完成時(shí)。

7、It's no pleasure doing... 做......沒有樂趣

考點(diǎn) 本句型中pleasure后用動(dòng)名詞，it作形式主語(yǔ)，真正的主語(yǔ)是后面的動(dòng)名詞。(類似的句型還有It's no use/good/point doing......)

例句 It is no pleasure looking through these any longer because nature is one thing that really must be experienced.

但是觀看這些已不再有樂趣，因?yàn)榇笞匀皇悄惚仨氂H身體驗(yàn)的。