機器
action
asphalt
brush
car
city
clean
cleaner
cleanliness
cleanup
dirty
ecology
environmental cleanup
equipment
ground
highway
hygiene
industrial
laundered
liquid
motion
municipal
orange
pavement
pouring
road
service
sidewalk
special
splash
splashing
sprinkler
stone
street
sweeper
sweeping
tank
technology
urban
washer
water
watering
wet
work