61. Since 1986 enrollments of African Americans, American Indians, and Hispanic Americans in full-time engineering programs in the United States has steadily increased, while the number of other students who enter the field has fallen.
(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
(E) have steadily increased, while that of other students who enter the field fell
选E?不过后面为什么不用完成时?是因为while吗? |