placido盘检查角膜弯曲度影像为椭圆形，则角膜为（）。
A.弯曲度正常
B.规则散光
C.不规则散光
D.圆锥角膜
参考答案：B
最可能的诊断为
A．反流性食管炎
B．食管癌
C．食管贲门失弛缓症
D．消化性溃疡
E．食管痉挛
Sometimes walking is even ______ than driving during the busy traffic time. [ ]
A. fast
B. faster
C. slow
D. slower
