英文關鍵字
accident
breakthrough
building
citizen
city
construction
damp
dirty
drain
drainage
dump
dwelling
ecology
emergency
environment
flow
fountain
hatch
hole
house
human
humid
industry
iron
jet
liquid
metal
moscow
people
pipe
pipeline
polluter
pollution
pour
problem
puddle
rusty
service
sewer
sewerage
site
stream
substance
system
truck
tube
urban
waste
water
wet