__________at the door before you enter the office，or you’ll be considered impolite
| A．Knocking | B．Knocked | C．Knock | D．To knock |
Edward, you have grown up. You should learn to make your own room_________.
| A．empty | B．noisy | C．dirty | D．tidy |
These natural disasters have warned us that everyone should start to protect the_________ immediately.
| A．amusement | B．development | C．environment | D．government |
There_________still some milk in the fridge. It’s not necessary to go to the store today.
| A．am | B．is | C．are | D．be |
—_________T-shirt do you like better, the red one or the blue one?
—I prefer the red one.
| A．How much | B．How many | C．Whose | D．Which |
Your English teacher has never lost his temper, _________he?
| A．has | B．hasn’t | C．did | D．didn’t |