舌苔形成的主要原因是（）
A.邪气过旺
B.正气不足
C.湿热下注
D.胃气薰蒸
E.饮食积滞
参考答案：D
---What's the difference between the first house and the second ?
---The first house has a garage while the second has _____.
A．no one
B．nothing
C．neither
D．none
目标规划问题中最优准则是检验数（）零。
