英文關鍵字
bottle
canal
chemical
conservation
damage
danger
debris
decay
dirty
disease
disposal
dump
ecology
ecosystem
environment
garbage
global
hazard
health
impact
impure
industry
infestation
junk
litter
nature
plastic
poison
pollute
polluted
pollution
recycle
river
rubbish
scrap
sewage
site
stream
toxic
trash
unhygienic
waste
water