The university estimates that living expenses for international students________around $8,450 a year，which________a burden for some of them.
| A．are；is | B．are；are |
| C．is；are | D．is；is |
— Will you go to the annual meeting to be held in Sweden from the 26-30th of August 2008?
— That depends on _______ I am invited.
| A．whether | B．if | C．whomever | D．why |
____is certain is ___prevention is more important than treatment .
| A．It;that | B．What;that | C．As;what | D．What;what |
Of one thing I am certain _____ hard work contributes to good results.
| A．as | B．what | C．which | D．that |
Being a good listener is a kind of quality and that’s ___ it takes to keep friendship.
| A．how | B．what | C．which | D．where |
Does it make any difference __________ he refuses or accepts the invitation?
| A．whether | B．which | C．if | D．that |