Question

【题目】We have to do our homework school nights.
A.at
B.on
C.in
D.by

Answer 1

【答案】B
【解析】在具体某一天的晚上用介词 on，on school nights 在上学的晚上，故选B。句意是：我们在上学的晚上必须做家庭作业。