四、it类
. Everyone knows that _______ is dangerous to play with fire, but _______ is difficult is to prevent children from playing with fire.
| A．it, it | B．what, what | C．it, what | D．what, it |
. 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 |
. – Don’t forget to come to my birthday party tomorrow.
– ________.
| A．I don’t | B．I won’t | C．I can’t | D．I haven’t |