---You have made great progress in your English study, haven’t you?
--- Yes, but much .
A. remains to do
B. is remained to do
C. remains to be done
D. is remained to be done
网友回答
A. remains to do
B. is remained to do
(答案→)C. remains to be done
D. is remained to be done
解析：考查remain的用法。remain是不及物动词，故排除B、D,根据意思，很多事情有待于被解决，故选C。