3. I smell something ____ in the kitchen. Can I call you back in a minute?

A. burning B. burnt C. being burnt D. to be burnt

4. At the beginning ofclass, the noise of desks _____ could be heard outside the classroom.

A. opened and closed B . to be opened and closed

C. being opened and closed D. to open and close

5. After a knock at the door, the child heard his mother's voice ____ him.

A. calling B. called C. being called D. to call

6. There is nothing more I can try ______ you to stay, so I wish you good luck.

A. being persuaded B. persuading C. to be persuaded

D. to persuaded

7. The country has already sent up three unmanned spacecraft, the most recent ____ at the end of last March.

A. has been launced B having been launched C. being launched D. to be launched

8.______ in the queue for an hour, the man suddenly realized he had left the cheque in the car.

A. waiting B. To wait C. Having waited D. To have waited

9. --- Can those _____ at the back of the classroom hear me?

--- No problem.