Lessons can be learned to face the future, ______ history cannot be changed.
| A．since | B．as | C．though | D．unless |
Not until I read your letter ________ the true state of the affairs.
| A．did I understand | B．had I understood |
| C．I understood | D．I had understood |
________ going to the program If You Are the One，she knew she had to be there or her mother would be unhappy.
| A．Although much she disliked |
| B．Much although she disliked |
| C．As she disliked much |
| D．Much as she disliked |
—Mary，turn the heat down，________ burn.
—OK.Mum.
| A．the cake will | B．or the cake will |
| C．will the cake | D．and the cake will |
Seldom ________ TV when he studied in senior high school.
| A．he watches | B．he watched |
| C．does he watch | D．did he watch |
Everything，unless otherwise ________，will go on as planned.
| A．stating | B．states | C．to state | D．stated |