Beijing is a city with many places of interest and tourists come here every year.A. milli

问题补充：

Beijing is a city with many places of interest and tourists come here every year.

A. million of

B. million

C. millions

D. millions of

答案：

A. million of

B. million

C. millions

(答案→)D. millions of

解析：考查短语millions of成千上万的，其它选项不和语法，故选D。