The principle of the heating system in this building is that pipes ________ hot water from the boiler to every part of it.
| A．consume | B．conduct | C．transmit | D．convey |
The students had the lights for almost three hours.
| A．to burn | B．burning | C．burnt | D．to be burning |
“Do you have any clothestoday, Master?” asked the servant politely.
| A．to wash | B．to be washed | C．washing | D．being washed |
it is to have a cold drink on such a hot day!
| A．What a fun | B．How fun | C．What fun | D．How a fun |
Some birds fly in winter and some stay in the north.
| A．south | B．the south | C．in the south | D．to south |
I don’t think math
| A．easily to be learned | B．easily to learn |
| C．easy to be learning | D．easy to learn |