A great many students have dropped out of school and now the number of our class has51. A.

问题补充：

A great many students have dropped out of school and now the number of our class has51.

A. increased to

B. increased by

C. reduced by

D. reduced to

答案：

A. increased to

B. increased by

C. reduced by

(答案→)D. reduced to

解析：考查短语辨析。由句意可以排除A,B两项；reduce to “减少到”后接减少后的总量；reduce by“减少了”后接纯减少的量或比率。