Though this question is very difficult，if you ________ trying you will find the right answer.
| A．keep up | B．keep on |
| C．keep out | D．keep off |
— Have you moved into the new house?
— Not yet. The rooms ________.
| A．are painting | B．are being painted | C．are painted | D．are being painting |
Living on Mars isn’t ________ as it sounds.
| A．as strange an idea | B．as idea strange |
| C．as a strange idea | D．as an idea strange |
Visitors ________ take an animal or any other item prohibited by the Expo Bureau to the Expo Park.
| A．needn’t | B．may not | C．mustn’t | D．will not |
One way to understand thousands of new words is to gain ________ good knowledge of basic word formation.
| A．/ | B．the | C．a | D．one |
．Sorry, sir. I broke the window glass, but I didn’t do that ______.
| A．on purpose | B．in purpose | C．with purpose | D．for purpose |