What is pollution?Pollution means a--- dirty or

What is pollution?Pollution means a___ dirty or
What is pollution?
Pollution means a___ dirty or harmful things to land,air,water and so on.It is bad for animals and plants,and it even makes people’s health in d___.In our daily life,we can see different kinds of pollution in many plaves.There are t___ main forms of pollution:land pollution,air pollution and water pollution.
Land pollution is caused by soild(固体的)waste,such as cans,bottles and some o___ things.It makes,the environment look very bad.However,air pollution is more s___ than land pollution.It is much worse in cities and towns,because of the fumes(废气)form traffic and the waste from human activities.When people d___ their cars,they produce fumes with CO2,NO2 and SO2.The fumes does great h___ to people’s health.And human activites can also the main r___ for water pollution.In some places,it has caused the shortage of fresh water.
Different kinds of pollutionwill c___ many health problems.People have realized they must change this serious situation.
We have only one e___.We must try our best to help protect our environment for the future wherever we are.