機器
barrel
business
capacity
car
cargo
chauffeur
cistern
clean
cleaner
cleaning
collector
dirt
dirty
drain
drainage
drive
dump
ecological
environment
equipment
filling
garbage
hatch
hose
industrial
industry
job
maintenance
nature
pipe
pollution
profession
pump
recycling
service
sewage
sewer
sewerage
special
street
tank
toilet
transport
truck
underground
waste
water
work
worker