问题补充:
---Look at those shoes, Mike!
---Wow! They look very cool, but I wonder .
A. how much are they
B. how much do they cost
C. if my parents will buy them for me
D. that my parents will buy them for me
答案:
A. how much are they
B. how much do they cost
(答案→)C. if my parents will buy them for me
D. that my parents will buy them for me
解析:if既可以引导宾语从句又可以引导状语从句。if充当宾语从句的连接词时,相当于whether,词义为“是否”,遵循宾语从句的时态规则,可根据语境选择任何时态;