大全3道题的困惑

1.        A new phenomena, which is visible at Managua’s major intersections, are waves of vendors and beggars, which include many children and mob cars at the stoplights.

(A) A new phenomena, which is visible at Managua’s major intersections, are waves of vendors and beggars, which include many children and

(B) Visible at Managua’s major intersections are waves of vendors and beggars with many children, new phenomena that

(C) A new phenomenon visible at Managua’s major intersections is waves of vendors and beggars, many of them children, who

(D) Phenomenally new waves of vendors, beggars, and many children are visible at Managua’s major intersections, which

(E) A wave of vendors and beggars, many of whom are children, are visible at Managua’s major intersections, where they are a new phenomenon and

 答案:（C）

2.        In good years, the patchwork of green fields that surround the San Joaquin
                            Valley town bustles with farm workers, many of them in the area just for the season.

(A) surround the San Joaquin
                    Valley town bustles with farm workers, many of them

(B) surrounds the San Joaquin
                    Valley town bustles with farm workers, many of whom are

(C) surround the San Joaquin
                    Valley town bustles with farm workers, many of who are

(D) surround the San Joaquin
                        Valley town bustle with farm workers, many of which

(E) surrounds the San Joaquin
                    Valley town bustles with farm workers, many are

答案:（A）

3.        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

答案:（D）

此三题的困惑,主要不是如何选出正确答案问题,在不考虑其它错误的前提下,为何1,2 两题,用的是 of  them, 而3用的是of whom. 请问这两种表达是否可以互换(在没有人称单复数错误的情况)?而且3中,如若有选项 one of them, 是否也正确?

请大侠指点!谢先!

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方便自己，方便他人，感谢您的理解和支持！

不好意思,我不清楚问什么发出来,跟我写的不一致,是标了题号的,而且后面还有我的疑惑的描述.我再发一遍吧.这里只所以把这三个题放在一块,就是因为为了比较它们.以下3道题出自大全987,具体题号见题目:

1.        A new phenomena, which is visible at Managua’s major intersections, are waves of vendors and beggars, which include many children and mob cars at the stoplights. (大全987-15)

(A) A new phenomena, which is visible at Managua’s major intersections, are waves of vendors and beggars, which include many children and

(B) Visible at Managua’s major intersections are waves of vendors and beggars with many children, new phenomena that

(C) A new phenomenon visible at Managua’s major intersections is waves of vendors and beggars, many of them children, who

(D) Phenomenally new waves of vendors, beggars, and many children are visible at Managua’s major intersections, which（C）

(E) A wave of vendors and beggars, many of whom are children, are visible at Managua’s major intersections, where they are a new phenomenon and

2.        In good years, the patchwork of green fields that surround the San Joaquin
                        Valley town bustles with farm workers, many of them in the area just for the season.(大全987-379)

(A) surround the San Joaquin
                    Valley town bustles with farm workers, many of them

(B) surrounds the San Joaquin
                    Valley town bustles with farm workers, many of whom are

(C) surround the San Joaquin
                    Valley town bustles with farm workers, many of who are

(D) surround the San Joaquin
                    Valley town bustle with farm workers, many of which（A）

(E) surrounds the San Joaquin
                    Valley town bustles with farm workers, many are

3.        Presenters at the seminar, one who is blind, will demonstrate adaptive equipment that allows visually impaired people to use computers.(大全987-584)

(A) one who

(B) one of them who

(C) and one of them who

(D) one of whom（D）

(E) one of which

把这3题放在一起比较,并不是为了仅仅得到正确答案,毕竟这3题都比较容易.只所以放在这,请教大侠,是关于,为什么1,2 用的是 of  them 来修饰前面的指代成分,而3 用的是of  whom来修饰前面的指代成分?到底什么时候用 of   them, 什么时候用of  whom?  这两者可以互换(假设指代的复数名词,避免them 不能指代单数代词的情况),还是有什么区别?另,如若题3,如若有one of them 这个选项,是否也正确?

谢先!