You can never imagine what great difficulty I have _____ your house.
| A．found | B．finding | C．to find | D．for finding |
We tried our best to ______, but she didn’t stop crying.
| A．call her up | B．cheer her up | C．give her up | D．wake her up |
By the time of last year, she ______ the piano for five years.
| A．learnt | B．has learnt | C．had learnt | D．will learn |
Tom likes the book ______ she borrowed from Jim.
| A．who | B．that | C．whom | D．whose |
—Listen! Peter is singing in the classroom!
—It _____ be him. He has gone back to his hometown.
| A．must | B．mustn’t | C．may not | D．can’t |
Keys _______ opening the lock in the door.
| A．used for | B．are used | C．are used to | D．are used for |