Airpollutionisabigproblem1.(affect)millionsofAmericans.2.(pollute)mainlybyindustriesandautomobilestheaircontainstoxic(有毒的)chemicals.Environmentalistspressurepoliticians3.(pass)stricterlaws.Howev

Question

Air pollution is a big problem 1.____ (affect) millions of Americans. 2. ____ (pollute) mainly by industries and automobiles the air contains toxic (有毒的) chemicals. Environmentalists pressure politicians 3. ____ (pass) stricter laws.

However the problems are too complex 4.____ (solve) easily.

Answer 1

1. affecting   2. Polluted3. to pass   4. to be solved