正常熟料中C3S含量高，则熟料的易磨性（）。
参考答案：好
1张50元可以换（ ）张10元，也可以换（ ）张5元，还可以换（ ）张20元和（ ）张10元。
—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
