问题补充:
—Where are Lucy and Lily?
—Oh , the two girls must a game in the garden now.
A. play
B. are playing
C. played
D. be playing
答案:
A. play
B. are playing
C. played
(答案→)D. be playing
解析:此题重点考查情态动词的用法,must为情态动词,后跟动词原形故排除B、C;根据语境:“---露西和莉莉在哪儿?”由now可知表示动作正在进行,故选D