The experiment, though they had tried their best, ________ to be a failure.
| A．turned up | B．turned out |
| C．turned in | D．turned on |
I don’t know _____,
| A．how can I finish my homework on time |
| B．how could I finish my homework on time |
| C．I can how finish my homework on time |
| D．how I can finish my homework on time |
The old pianist requested that he ____ the piano in the public again.
| A．play | B．played |
| C．would play | D．was going to play |
It is not who is right but what is rightis of importance.
| A．which | B．it |
| C．that | D．this |
You must watch carefully everything _____ the teacher does in class.
| A．where | B． who |
| C．what | D．that |
She didn't come to his birthday party just_____ what he had said to her the day before.
| A．because | B．because of |
| C．as a result | D．thanks for |