BBC news 2009-07-29 加文本

1.Troops in Nigeria have been shelling the headquarters of a radical Islamist group, which is accused of being behind three days of violence across five northern states, which has left at least 100 people dead.

这句话的前半部分是主干，后面的which is accused of是定语从句，修饰Islamist group。which has left……也是定语从句，修饰violence。

2.Now that is a big deal, I would not have chosen her but I understand why President Obama did.

would not have是虚拟语气。表示与过去的事实相反，条件状语从句中的谓语动词用过去完成时，主句中的谓语动词则用“would / should / might / could + have +过去分词”。如：

If he had taken my advice, he would have succeeded in the competition.

3.The settlement still needs to be approved by a U.S. court.

need还有一个比较特殊的用法。

need doing表示“需要被做”，主语一般为物，相当于need to be done；need to dosth．表示“需要做某事”，主语一般为人。类似此用法的动词还有want(需要)等，例如：

(1)My car needs mending。=My car needs to be mended．

我的小汽车需要修理。

(2)We need to study hard．

我们需要努力学习。