问题补充:
—Why do you look sad?
—There are so many problems .
A. remaining to settle
B. remained settling
C. remaining to be settled
D. remained to be settled
答案:
A. remaining to settle
B. remained settling
(答案→)C. remaining to be settled
D. remained to be settled
解析:由于remain是不及物动词,故应用现在分词remaining,相当于定语从句that remains;动词settle置于remain之后,应用动词不定式的被动结构来表示动作还未完成。