-When can you come to school this afternoon ? about seven . A. OnB. AtC. OfD. In

问题补充：

---When can you come to school this afternoon ? --- about seven .

A. On

B. At

C. Of

D. In

答案：

A. On

(答案→)B. At

C. Of

D. In

解析：在具体时刻要用介词at。