____________ the weather has improved, the game will be held as planned.
| A．While | B．Since | C．If | D．Unless |
The sun heats the earth, ___________ is very important to living things.
| A．that | B．what | C．which | D．where |
I will visit you if Father ______ me.
| A．let | B．lets | C．is letting | D．will let |
The policeman warned the drive ________ so carelessly.
| A．never to drive | B．to never drive | C．to not drive | D．doesn’t drive |
—Can I use your laptop for a while?
—; anyhow I am not using it now．
| A．That's OK | B．By all means | C．It doesn't matter | D．Use it |
Only after Helen moved to Australia ______ how important she was to me .
| A．I had realized | B．had I realized | C．I did realize | D．did I realize |