. It has always been the _____ of our firm to encourage workers to take part in social activities.
| A．plan | B．campaign | C．procedure | D．policy |
The message is very important, so it is supposed _______ as soon as possible.
| A．to be sent | B．to send | C．being sent | D．sending |
Visiting _______ Great Wall is ________ unforgettable experience to me.
| A．/; / | B．/; an | C．the; an | D．the; / |
---- Do you surf the Internet a lot？
---- Well,_______, I’m too busy with work to surf the Net.
| A．all right | B．I have no idea | C．at last | D．to tell you the truth |
with so much homework to do，David told his sister_____so much noise.
| A．to make not | B．not to make | C．not making | D．making not |
it was because of his kind nature _______I fell in love with Peter.
| A．before | B．when | C．that | D．since |