问题

Only when he arrived home _____ that he had left his key in the office.
A:will he realize
B:he did realize
C:did he realize
D:should he realize
B:he did realize
C:did he realize
D:should he realize
正确答案是:
同类题型
Mary loves singing so much. She ________ after school very often.
______ a certain doubt among the people as to the practical value of the project.
I am going to take part in the piano competition next week.—_______
It was not until dark _____ he found _____ he thought was the correct way to solve the problem. [ ]