when they got to the school,they were just in time__the first lesson.A on B for C at D to

问题描述:

when they got to the school,they were just in time__the first lesson.
A on B for C at D to

B。for .
just in time for sth. 刚好来得及做某事.
如:I was just in time for school.

答案:B(for),词组be in time for sth, 来得及/赶上某件事,这句话的意思:当他们到学校时,他们正好赶上第一节课。

选B
be in time for sth来得及干某事
当他们到达学校,他们正好赶上第一节课