浜辺
beautiful
blue
brown
city
clean
construction
danger
dirty
drain
dump
environment
flow
flowing
garbage
grass
green
greenpeace
industry
lake
line
metal
natural
nature
oil
old
open
pipe
pipeline
planet
plant
pollute
pollution
rain
river
rust
rusty
sewage
sewer
sky
stream
substance
toxic
trees
tube
wall
waste
wastewater
water
world