英文關鍵字
bad
cement
chemical
concrete
crisis
danger
dirty
drain
drainpipe
dump
ecology
environment
environmental
erosion
factory
flow
flowing
fluid
garbage
green
industrial
industry
influence
irrigation
liquid
nature
old
outlet
pipe
pipeline
pollution
pouring
power
red
sewage
sewer
sky
smell
stream
technology
toxic
treatment
tube
urban
warming
waste
water
waterfall
waterway