students in China are learning English at school.A. Many thousand B. Thousand of C. Thou

问题补充：

students in China are learning English at school.

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

答案：

解析：句意：成千上万的中国学生在学校学英语。短语thousands of 成千上万的，注意thousand 要用复数形式；但在具体的数字中thousand不用复数形式，例如three thousand 三千；结合语境故选C。