students in China are learning English at school.A. Thousand of B. Thousands of C. Many t

问题补充：

students in China are learning English at school.

A. Thousand of B. Thousands of C. Many thousand

答案：

解析：句意:中国成千上万的学生都在学校学习英语。当thousand前没有具体数字的时候，可以用复数，后加上of+名词，根据句意故选B。