20. The new plan has been put forward _________ we will move to the new campus
next term.
A. as B. while C. when D. that
19. I hope I will not be called on in class as I’m not yet _____ prepared.
A. attentively B. readily C. actively D. adequately
18. It must be he that has stolen Mr. Smith’s purse, _______?
A. hasn’t he B. isn’t he C. mustn’t it D. isn’t it