英文關鍵字
agriculture
bore
close
concept
concrete
contamination
danger
dirty
drain
drainage
drill
drilling
drop
dump
ecology
environment
environmental
flow
flowing
fluid
garbage
industrial
industry
liquid
macro
mud
muddy
pipe
polluted
polluter
pollution
pour
process
river
sewage
sewer
sewerage
sluice
stream
substance
system
toxic
treatment
tube
unclean
waste
water
well
work