Don't make friends with such young men ____?don't work hard．
A．that B．as C．who D．they
此题应选B.容易误选A,C.句中的as是关系代词,句意为：不要跟工作不努力的人交朋友.此句也可换成：
正：Don't make friends with young men who [that] don't work hard．
正：Don't make friends with those young men who[that] don't work hard．
as用作关系代词（用作主语或宾语）,主要用法如下：
1．用在such,same等之后,引导限制性定语从句：
Don't talk about such things as you don't understand．不要谈你不懂的东西.
Such men as（=Those men who） heard him praised him．听过他谈话的人都称赞他.
I told him the same story as you told me．我给他讲的故事与你给我讲的故事一样.
2．单独用作关系代词,引导非限制性定语从句,可放在主句之前（常译为“正如”）或之后（常译为“这一点”）：
As has been said before,grammar is not a set of dead rules．
正如前面所说,语法不是一套死规则.
He was a foreigner,as （=which）I knew from his accent．他是个外国人,这从他的口音可以得知.
If he comes late,as is usual,for another time,we will not re－ ceive him．如果他再像以往那样迟到,我们就不接待他了.