public place Place of assembly or recreation Includes(7 classes and 28 kinds) hotel. restaurant bar public bathroom, barber shop and beauty shop public place of entertainment gymnasium, swimming place
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
Water is essential to life Our health depends on the quality and safety of water Water pollution and poor water resources are the big problem in China There are 700 million people in China, whose drinking water is not safe
