These continual _____ in temperature make it impossible to decide what to wear.
| A．alterations | B．vibrations | C．waves | D．fluctuations |
John, look at the time，________you play the piano at such a late hour?
| A．Must |
| B．Can |
| C．May |
| D．Need |
—Are you coming to Jeff's party?
—I'm not sure. I________go to the concert instead.
| A．must |
| B．would |
| C．should |
| D．might |
Mr. Bush is on time for everything. How________it be that he was late for the opening ceremony?
| A．can |
| B．should |
| C．may |
| D．must |
Tom, you________leave all your clothes on the floor like this!
| A．wouldn't |
| B．mustn't |
| C．needn't |
| D．may not |
There________be something wrong with my computer.
| A．should |
| B．must |
| C．will |
| D．can |