问题补充：
These shoes look very nice. I wonder .
A. how much they are cost
B. how much do they cost
C. how much are they cost
D. how much they cost
答案：
A. how much they are cost
B. how much do they cost
C. how much are they cost
(答案→)D. how much they cost
解析：“这些鞋子太好看了，不知道多少钱。”考察宾语从句，从句用陈述语序，答案D。
