1. Air pressure forces the water through the pipe.
   空气压力使水通过管道.
2. That air has pressure is known long ago .
   空气有压力这是人们早就知道的。
3. Air pressure decreases with altitude.
   气压随海拔高度的增加而下降。
4. The air pressure is falling.
   气压在降低.
5. We made an experiment to explain air pressure.
   我们做过一个实验来解释空气的压力。

　1个名词解释