问题

He kept yawning in class this morning. That is _____he stayed up late doing his homework last night.
A:why
B:how
C:because
D:whether
B:how
C:because
D:whether
正确答案是:
同类题型
______ Tom at home this afternoon— Yes. He _________ go out on Sunday afternoons.
I didn’t see her in the meeting room this morning. She _______ at the meeting.
His mother asked him ___ watch TV ___ he finished his homework.
______ eggs do you need for the soup — Well,one is probably.
You ________ reach him on his mobile now — his mobile is still under repair.