Atmospheric sphere Definition: the air layer which surround the surface of earth and circumrotate with earth. (包围地球表面并随着地球旋转的空气层) The thick is around 2000km~3000km. The character of physics and chemistry of atmospheric sphere is change with height
Ellipsis I In compound sentences 电压的单位是伏特,电流的是安培。 Voltage is measured in volts and current in amperes. 地球吸引月球,月球也吸引地球 The earth attracts the moon and the moon the earth