英文關鍵字
attitude
background
causes
city
concept
concrete
crisis
damaged
danger
dirt
dirty
drain
drainage
environment
environmental
floor
flow
garden
grass
green
ground
grow
house
idea
industry
leaf
leaves
liquid
moss
mossy
motivation
mud
natural
nature
outdoor
outside
pipe
pipeline
pipes
plant
pollution
positive
river
sewage
sewer
stream
survival
thinking
trash
tube
vines
wall
waste
wastewater
water
wet