By the time my mom to our school all others of my class for home.A. got leftB. got ha

问题补充：

By the time my mom to our school, all others of my class for home.

A. got, left

B. got, had left

C. had got, had left

D. had got, left

答案：

A. got, left

(答案→)B. got, had left

C. had got, had left

D. had got, left

解析：“等到我妈妈到达学校的时候，班上其他同学都已经离开回家了”，由此可知妈妈是过去到达学校的，故用一般过去时态，妈妈到达学校的时候，同学们已经离开回家了，是过去的过去，用过去完成时。