There are three students in their school.A. thousands ofBthousand ofCthousandsDt

问题补充：

There are three students in their school.

A. thousands of

Bthousand of

Cthousands

Dthousand

答案：

A. thousands of

B. thousand of

C. thousands

(答案→)D. thousand

解析：考查数词的用法。hundred/thousand/million/billion等前面有具体数字时，不能用复数形式，且不与of连用；hundred/thousand/million/billion单独使用，表虚数时，常用复数形式，且可以与of连用。根据three排除A、B、C。故选D。