英文關鍵字
animals
aquatic
background
bag
canal
contamination
damage
decayed
dirt
dirty
ditch
ecosystem
environment
fish
floats
garbage
grass
green
harmful
issues
junk
life
litter
mixed
nature
oily
outdoor
park
plants
plastic
poison
polluted
pollution
pond
problem
puddle
reflection
rubbish
sewage
slough
stains
surface
swamp
toxic
trash
unclean
waste
wastes
water