194. Presenters at the seminar, one who is blind, will demonstrate adaptive equipment that allows visually impaired people to

use computers. (A) one who (B) one of them who (C) and one of them who (D) one of whom (E) one of which

The subject, presenters, must be followed by a limiting appositive _

such as one of whom, that identifies an indi­vidual from among a larger

group. Choice D is best: one of whom best serves an appositive to the

subject, presenters, because the phrase means "one from among several

or many." Choice A, one who, is unacceptable because one who cannot

refer to the plural presenters. Choices B and C are ungrammatical

because who competes with one as the subject of is. Choice E employs

which, a relative pronoun that does not refer to people (presenters),

but only to things.

不理解为什么用ｗｈｏｍ　，　谁能教教

这句话的主语是：Presenters at the seminar 谓语是：will demonstrate XXX 主语和谓语之间是限制性同位语从句----说明presenters的情况。one of whom就充当这个角色，意思是其中有一个盲人。 如果搂主还不明白，把one去掉，直接用，who are blind; 或者 all of whom are blind, -------一群盲人。这样是不是更清晰了。