英文關鍵字
bottle
chemical
chemistry
cleanup
cruel
danger
dirt
dirty
dump
dumping
ecology
environment
garbage
health
horror
impure
junk
lake
material
nature
ngo
oil
plastic
pollution
poor
poverty
problem
problems
river
rotting
rubbish
sea
sewage
smelling
stream
trash
ugliness
unhealthy
unhygienic
waste
water