A:2-1
B:22
C:1
D:12
①隋 ②唐 ③明 ④清
-What are you doing?
-I'm s____ the floor. It's dirty.
平仄协调,字数相等,结构相同,是对仗的基本要求。下列各组成语中,构不成对仗的一项是 ( )