题目

当细胞代谢旺盛、生长迅速时，结合水与自由水的比值将 A、保持不变    B、降低    C、升高    D、不能确定 答案：B--Hi, Lydia. Are you going to the concert on Friday?--I’d like to. But there are so many problems ____.   A. remaining to be settled                 B. remained settlingC. remaining to settle                        D. remained to be settled