---Hey,can I ask you a favor?
---Sure, ________.
| A．here you are | B．just as I thought |
| C．how is it going | D．what can I do for you? |
Recently a new social issue has been brought to everyone’s attention _____food additives are abused．
| A．when | B．whether | C．that | D．which |
While the police have already done a lot of investigation, much evidence _____.
| A．is remaining to be confirmed | B．remained to be confirmed |
| C．is remained to be confirmed | D．remains to be confirmed |
_____ on everyday practice, progress in English is a goal which can be achieved．
| A．Based | B．Basing | C．Having based | D．Being based |
Look out! Keep away from the house, _____ the roof is under repair．
| A．whose | B．which | C．of which | D．where |
．You’d better get the problem solved as soon as possible ______ it becomes out of control．
| A．when | B．before | C．since | D．unless |