GWD-24-20~~一点我自己的理解。

GWD-24-Q 20:

According to a 1996 survey by the National Association of College and University Business Officers, more than three times as many independent institutions of higher education charge tuition and fees of under $8,000 a year than those that charge over $16,000.

A.      than those that charge

B.       than are charging

C.      than to charge

D.      as charge

E.       as those charging

这里more than three times 只是起到了≥3的作用，实际上真正其作用的是as many independent institutions of higher education charge tuition and fees of under $8,000 a year than those that charge over $16,000.

那么就要分析这句话里面的真实含义：

A charges as many as B (charges). 含义是A 和B charge 的一样多

As many A charges L as B.   含义是
            charge L的
            A 和B一样多.

那么就看出来这两个的区别了第一句强调的是A B charge的内容一样多

                          第二句强调的是A B 一样多

而本题显然属于第二种。Those charging over $16,000 中的charging over $16,000显然是修饰those的。