dialogue: #Person1#: Well, no one could survive without water, but you see pollution has been making more and more water unable for drinking.
  #Person2#: Yeah. Water pollution has for a long time been a major concern among the environmental issues.
  #Person1#: But what are the sources of water pollution?
  #Person2#: They could generally be divided into two categories
  #Person1#: Well, direct ones are the pollution directly from factories, refineries waste treatment plants etc. , aren't they?
  #Person2#: Yeah. They are emitted directly into urban water supplies.
  #Person1#: But what about the indirect ones?
  #Person2#: Indirect sources include contaminants that enter the water supply from soils or groundwater systems and from the atmosphere via rainwater.
  #Person1#: I see. For the sake of us all, we should be an active participator in the prevention of it.
  #Person2#: Sure. It's an issue asking for everyone's participation.
summary: #Person1# and #Person2# talk about water pollution and its direct and indirect sources. They agree they should be an active participator in the prevention of it.
topic: water pollution