It shows that ______ knowledge of first aid can make _____ real difference.
| A．a. /; a | B．/; the |
| C．the; the | D．the; a |
. He must be curious about everything in the lab, for this/that/it is the first time that he has been there, ________?
| A．isn’t he | B．mustn’t | C．isn’t it | D．hasn’t he |
. You have must practiced speaking English for a long time before the contest is held, ________?
| A．mustn’t you | B．didn’t you | C．haven’t you | D．isn’t it |
. Mary is barely a diligent girl, as it is the fourth time she has been sleeping in class, ________?
| A．is she | B．isn’t she | C．isn’t it | D．hasn’t she |
. Brian told you that there wasn’t anyone in the room at that time, ________?
| A．was there | B．wasn’t there | C．didn’t be | D．did he |
. I think she always disagrees with him, ________?
| A．do I | B．don’t I | C．does she | D．doesn’t she |