问题
选择题
“That VCD you bought ____ very expensive” . “Do you know ____ ? ”
A．ought to be ; how much it cost
B．may be ; how much it costs
C．must be ; how much it cost
D．can be ; how much doesn''t it cost
答案
C。
根据语序排除D，A不合语意，B中第二空时态不符。