_______the large population, we’ll _________ energy and water.
| A．Because; be short of | B．Because of; be short of |
| C．Because; be short for | D．Because of; be short for |
The girl was often heard ______ happily in her room.
| A．sing | B．to sing | C．singing | D．sings |
The key ____ for opening the door of the room.
| A．uses | B．is using | C．is used | D．used |
_____ shouldn’t have part-time jobs because they are too young.
| A．Thirteen years old | B．Thirteen-year-old | C．Thirteen-year-olds | D．Thirteen year olds |
_____ lovely day!
| A．What a | B．What | C．How a | D．How |
All the new books _______ to the poor village next month.
| A．were sent | B．will be send | C．are sent | D．will be sent |