1.weak,chest,Anyway,gas,produce

　　2.D,C,C,D,D

　　3.E,A,D,C,B

　　4.few,strange,how,forests,gardens,

　　rainwater,pollute,popular,must,change.

　　5.(1)air,water,soil,pollution.

　　(2)thegovernmenthaspassedlawstopreventtheenironmentfrombeingpolluted

　　(3)pollutedaircancauseillnessandeverdeath

　　(4)thepollutedwater,litter,badgasand

　　chemical

　　(5)insomesupermarkets,stopassistantscannotuseplasticbagstopackfruits

　　(6)environmentalpollutionisoneofthemostseriousproblemsforpeople.

　　(7)environmentalpollution.