The fire，believed to due to illegal construction on the building’s roof, was brought
under control after an hour．
| A．have occurred | B．occur |
| C．have been occurring | D．be occurring |
Don't worry. I'm sure things will get better.
| A．in time | B．on time |
| C．at times | D．at the time |
Tom was about to close the window ________ his attention was caught by a bird.
| A．when | B．it | C．and | D．till |
With so many noises from the busy traffic in the street, I couldn’t______ and do my research work.
| A．put down | B．set down |
| C．cut down | D．settle down |
You _______ here last week if you were really worried about your work.
| A．ought to come | B．ought to be coming |
| C．ought to have come | D．ought have come |
The wooden house______ by many trees_______ south.
| A．surrounded; facing | B．surrounded; faces |
| C．surrounding; facing | D．surrounding; faces |