---Listen! The fire engine is roaring! (消防车吼叫)
--- Oh, there ______ be a fire somewhere. How terrible!
| A．should | B．must | C．have to | D．will |
They use computers to keep the traffic _________ smoothly.
| A．being run | B．run |
| C．to run | D．running |
I got to the office earlier that day,________ the 7:30 train from Paddington.
| A．caught | B．to have caught |
| C．to catch | D．having caught |
The manager _______ his workers how to improve the program since 9 am.
| A．has told |
| B．is telling |
| C．has been telling |
| D．will have told |
I can ______ the house being untidy, butI hate it if it’s not clean.
| A．come up with |
| B．put up with |
| C．turn to |
| D．stick to |
According to scientists, our mental abilities begin to __________ from the age of 27 after reaching the highest level at 22.
| A．differ | B．shrink | C．fail | D．decline |