We can’t continue to pretend that the problem of pollution doesn’t___________in this city.
| A．exist | B．live | C．be | D．survive |
The thief had himself _____ by the police when he was trying to break into the hotel.
| A．to spot | B．to be spotted | C．spotted | D．being spotted |
The reason was _____ I was busy with my work at that time.
| A．why | B．because of | C．that | D．what |
. He misunderstood _____ I said.
| A．that | B．when | C．where | D．what |
. The trouble is _____ we are short of hands.
| A．what | B．that | C．how | D．why |
The guide showed the travelers _____ of the factory.
| A．in | B．out | C．off | D．around |