機器
action
asphalt
automatic
automotive
broom
brush
car
city
clean
cleaner
cleanliness
cleanup
clear
closeup
dirt
dirty
dust
dusty
environment
equipment
garbage
hygiene
machinery
mechanical
municipal
neat
nobody
orange
pavement
public
purity
road
rubbish
service
special
street
street cleaner
sweep
sweeper
sweeping
technology
truck
urban
vehicle
wash
water
wheel
work