The disease failed to _______ to the new drugs the doctor used.
| A．respond | B．reflect |
| C．reply | D．reduce |
It’s a very kind offer, but I really _____ accept it.
| A．mustn’t | B．needn’t |
| C．can’t | D．don’t |
That car nearly hit me; I ______.
| A．might be killed | B．might have been killed |
| C．may be killed | D．may been killed |
“I called you yesterday. A woman answered, but I didn’t recognize her voice.” “Oh, it _____ my aunt Jean.”
| A．must be | B．must have been |
| C．might be | D．can have been |
“I thought you wouldn’t mind.” “Well, as a matter of fact I don’t, but you _____ me first.”
| A．should ask | B．should have asked |
| C．must ask | D．must have asked |
You _____ be right, but I don’t think you are.
| A．can | B．could | C．must | D．should |