A five­year­old boy can speak two foreign languages, which surprises all the people present.

　　一个五岁男孩会讲两门外语，这令在场的所有人感到惊讶。

　　Bob's father, who worked on the project, spent four years in Egypt.

　　鲍勃的父亲从事这项工程，在埃及度过了四年。

　　As can be seen from his face, he is quite pleased.

　　从他的脸上可以看出来，他非常高兴。

　　[名师点津]　由as, which引导的非限制性定语从句，as和which可指代整个主句或主句所表达的整个意思，相当于and this或and that，且在定语从句中都可以作主语和宾语。但不同之处主要有：

　　(1)as引导的定语从句可置于句首，而which不可。

　　(2)as后常接expect, know, report, say, see等动词的主、被动语态句，有"正如，就像"之意；which常翻译为"这一点"。

　　[即时演练1]

　　(1)用适当的关系代词填空

　　①Have you seen the film Warcraft(《魔兽》), whose leading actor is world famous?

　　②My friend, who has served on the International Olympic Committee all his life, is retiring next month.

　　③As we all know, China is a developing country.

　　④My uncle gave me a book, the cover of which is very beautiful.

　　⑤Peter, whom you met in London, is now back in Paris.

　　(2)完成句子

　　①The boy, whose_father_is_an_engineer,_studies very hard.

　　那个小男孩学习很努力，他的父亲是位工程师。

　　②These apple trees, which_I_planted_three_years_ago,_have not borne any fruit.

　　这些苹果树是我三年前栽的，还没有结过果实。

　　3．关系副词引导的非限制性定语从句

　　当先行词指时间或地点时，用when, where引导非限制性定语从句，在定语从句中作状语。why不引导非限制性定语从句，但可用for which代替。

　　We will put off the outing until next week, when we won't be so busy.

　　我们将把郊游推迟到下个星期，那时我们就不会那么忙了。

　　Many children go to a day care centre, where they can learn games.

很多孩子上日间托儿所，在那儿他们可以学习游戏。