Environmental (1)____________ is when people make their surrounding dirty in many different ways. They make the air dirty by (2)___________ gases and smoke, make the water dirty by putting chemicals and other harmful things in it, and harm the soil by using too many fertilizers and pesticides. People also pollute their surrounding in other ways. (3)_________, they make the land and water look bad by throwing garbage and litter anywhere. They use machines and vehicles (4)_________ make loud and annoying noise, which fills the air. 1. A.Polluted   B.polluter   C.Pollute   D.pollution 2. A.adding   B.making   C.releasing   D.putting 3. A.because  B.for example  C.such as  D.although 4. A.which   B.who  C.whose  D.whom