I'd appreciate __________ if you would like to teach me how to use blog and twitter on the Internet.
| A．that | B．it |
| C．this | D．what |
So sudden ________ that the enemy had no time to escape.
| A．did the attack | B．the attack did | C．was the attack | D．the attack was |
Occasions are quite rare ____ I have the time to spend a day with my kids.
| A．who | B．which | C．why | D．when |
_____ was most important to her, she told me, was her family.
| A．It | B．This | C．What | D．As |
He didn’t make ______clear when and where the meeting would be held?
| A．this | B．that | C．it | D．these |
-Is Jack on duty today?
-It ____ be him. It’s his turn tomorrow.
| A．mustn’t | B．won’t | C．can’t | D．needn’t |