His job was to achieve the release of the hostages, a task he successfully accomplished. 他的职责是力争人质的释放，这一任务他成功地完成了。

请问句中的a task 是什么成分？（我知道它后面的he successfully accomplished 是定语从句）这个 a task 是同位语吗? 修饰 job？如果是的话，同位语可以离被修饰的名词这么远吗?

【答】task 是the release of the hostages 的同位语，不是job 的同位语。这不是说因为job离得远就不能成为同位语，而是task 跟job 构不成同位关系。

两个具有“同位关系”的词语，在意义上须具备“解释和被解释”和“说明和被说明”的关系。job 跟task 不存在这层关系，而且内容有重叠。

此外，task 指具体的一项任务，而job 往往是指一项长期的工作和职责。所以，“释放人质”这次活动，应该是一项具体的任务（task）。

同位语的分隔，一般指同位语从句的分隔。以下句子中，句末的同位语从句被红色部分分隔开来。例如：

There is a new problem involved in the popularity of private cars that road conditions need to be improved.

Information has been put forward at the meeting that more middle school graduates will be admitted into universitie

The question sometimes comes to my mind whether it was worth the effort.

There is no doubt, in my opinion, that what matters is not one’s looks, but one’s inner thoughts

Mr. Smith left word with his assistant that he had returned to his own country for winter holidays.