It won’t work:,it’s a bad idea,and secondly it’ll cost too much.
A. above all
B. to begin with
C. first of all
D. at first
网友回答
A. above all
(答案→)B. to begin with
C. first of all
D. at first
解析：题干中secondly暗示着所填短语表示“首先”。above all侧重于表达“最重要的是……”;first of all一般不用于“首先……，其次……”的列举;at first表示“起初”，只有to begin with 符合题意。