Module 5 Newspapers and MagazinesSection Ⅲ Grammar 时间状语从句和原因状语从句

　　语法图解

　　探究发现

　　①When he was orbiting in the capsule, he took photographs of planet earth.

　　②When Yang landed, Premier Wen Jiabao telephoned the Control Centre to offer his congratulations.

　　③Whilehe was travelling in space, Yang spoke to two astronauts aboard the International Space Station.

　　④Whenyou read a newspaper article in English, read the sub­headingsbefore you start ...

　　⑤The manager didn't attend the party because he was ill.

　　⑥"As you have asked me so nicely，" said Sharon, "I'd be delighted to sign your arm."

　　⑦Sinceno one else saw the aliens, not many people believe Mr Bates.

　　⑧Now that I have made this first visit, I hope I can come many more times.

　　[我的发现]

　　(1)例句①②③④中的连词引导时间状语从句；例句⑤⑥⑦⑧中的连词引导原因状语从句。

　　(2)when引导时间状语从句时，从句中的谓语动词和主句谓语动词所表示的动作同时发生，如例句①④；也可以在其之前发生，如例句②。

　　(3)while引导的时间状语从句中的谓语动作必须是和主句谓语动作同时发生，如例句③；而before引导的时间状语从句中的谓语动作必须在主句谓语动作之前发生，如例句④。

　　(4)because引导原因状语从句时，可以置于主句之前，也可以置于主句之后，如例句⑤；而as, since, now that引导原因状语从句时经常置于主句之前，如例句⑥⑦⑧。