Mary runs ______ among them.

Mary runs ______ among them.
A、the fastest
B、the most fast
C、most fastly
D、most fast
【正确答案】：A
【题目解析】：A. The fastest, 通常单音节,双音节最高级后+er /est。三个或三个音节以上+more /most。一个元音发音为一个音节，称为单音节.如，high 一个音节higher /highest。 beautiful三个音节(more beautiful most beautiful)