_____ is known to us all is that America is a developed country _____ the First World.
| A．Which; belonging to | B．as; belonging to |
| C．what; belonging to | D．It; belonging to |
. Don’t have the lights ______ all day long. It is a waste of electricity.
| A．burn | B．burned | C．burning | D．to burn |
. Either you or the headmaster ______ the prizes to the gifted students.
| A．is handing out | B．are to hand out | C．are handing out | D．is to hand out |
. The 2010 Shanghai World Expo is well worth ______.
| A．visit | B．visited | C．to visit | D．visiting |
I am interested in traveling. It is ______ but ______.
| A．interesting; tiring | B．interested; tired |
| C．interesting; tired | D．interested; tiring |
The windows haven’t cleaned for a long time. They need ______.
| A．to clean | B．to be cleaned | C．cleaning | D．B and C |