可采煤层
参考答案：
达到国家规定的最低可采厚度的煤层
病室内温度过高时，使患者( )。
A．肌肉紧张B．感到烦躁C．头晕、食欲减退D．闷热、难受E．呼吸道黏膜干燥
We looked at each other surprise when we heard a bird singing "Happy birthday to you ". [ ]
A. in
B. to
C. by
D. at
