这句话中的which为什么不能用that

问题描述:

这句话中的which为什么不能用that
The term “liberal arts ” comes from the Latin root liber,meaning “free.” This term originally referred to seven fields of study which(这个为什么不能用that),in ancient Greece,were considered arts of the mind,in contrast to the manual or mechanical arts.

可以用that的,一般能用which 的都能用that,但是能用that的不一定都能用which书上选的which 没选that恩,理论上which和that都可以,但是因为that太普遍了,which才是出这题的目的所在,是为了让答题人明白which在承接两句中的作用。that引导的句子可以在从句中做成分这句话总没错吧,至少我当年是这么学的。。。