—The meeting is about to start, yet the speaker hasn’t turned up.
— No one knows ____.
| A．what the matter is | B．what is the wrong |
| C．what is the matter | D．how matter stood |
—Hello, can I speak to Mr. Smith?
—I’m sorry, but it is 3 weeks _____ he worked here.
| A．before | B．since | C．after | D．while |
—It’s hard to believe that Jack should have fought with the policeman.
—Yes. If one ____ ask for trouble, it can’t be helped.
| A．may | B．need | C．must | D．should |
—When did your brother begin to show his interest in medicine.
—It was a Saturday _____ he noticed his classmate experimenting on a frog in the lab.
| A．that | B．what | C．when | D．which |
The Browns held _____ they called “family day”once a year.
| A．that | B．what | C．which | D．when |
______ what the six blind men said sounded!
| A．How foolishly | B．How foolish |
| C．What foolishly | D．What foolish |