[讨论]大全646（OG11里的061） while的问题

(A) has steadily increased, while the number of other students who enter the field has fallen

(B) has steadily increased, while other students entering the field have declined in number

(C) increased steadily, while there was a decline in the number of other students entering the field

(D) have steadily increased, while the number of other students entering the field has fallen（D）

(E) have steadily increased, while that of other students who enter the field fell

看这道题的解释是考agreement的，俺也选对了。但是对题目本身有疑问。这里的since应该是作为conj引导一个状语从句，但是while应该也是一个conj引导一个从句，那么这句话岂不没了主句了？我刚开始做的时候，一直在想找个去掉了while的选项，可是5个选项都没有我理想的那个，只好退而求其次选了D。

     有知道的XDJM指点指点啊～～～多谢

哦，多谢LS的，看了半天总算看明白了。

这里的since应该是充当的prep，而它跟1986一起“since 1986"做的主句的状语。那么其实就是这个句子可以改为 Enrollments of African Americans, American Indians, and Hispanic Americans in fulltime engineering programs in the United States have steadily increased since 1986, while the number of other students who enter the field has fallen. 也没问题啦～～～