—What do you usually do weekdays after school?—I usually read books.A. in B. at C. on

问题补充：

—What do you usually do weekdays after school?

—I usually read books.

A. in B. at C. on

答案：

解析：句意：——在平时在放学后你经常做什么？——我经常读书。in 在……里；at 在； on 在具体某一天。on weekdays在平时。故选C。