Every year people go to visit their factoryA. a thousand of B thousandsC. thousand of D.

问题补充：

Every year, people go to visit their factory

A. a thousand of B thousandsC. thousand of D. thousands of

答案：

解析：考查数词。数词hundred, thousand, million等后面跟of时，要变复数。排除C。thousand前接具体数字时，后面不能跟of，排除A。thousands后要加of，排除B。