It was not yet dawn the boy got to the school.A. whenB. thatC. beforeD. until

问题补充：

It was not yet dawn the boy got to the school.

A. when

B. that

C. before

D. until

答案：

(答案→)A. when

B. that

C. before

D. until

解析：考查时间状语从句。句意：当这个男孩到达学校的时候，天还没有亮。When引导的是一个时间状语从句。本题容易错选B项，会认为这是强调句型，但是本句中的yet dawn不能在句中单独做时间状语。故A正确。