这道题为什么选B?Tom had won a ____ prize before he left.

问题描述:

这道题为什么选B?Tom had won a ____ prize before he left.
B.three-million pound
C.three million pounds
D.three-million-pounds

C million 后要加of
D 没这种形式
选B three-million 为一个复合词 后面不用加S