英文關鍵字
asphalt
beacon
broom
brush
car
city
clean
cleaner
cleanliness
clear
collector
concrete
dirt
dirty
driving
dust
environment
evening
garbage
land
machine
motion
night
orange
pavement
pollution
road
rotate
rotating
rubbish
service
sidewalk
street
sweep
sweeper
sweeping
traffic
trash
truck
urban
vacuum
vehicle
wash
waste
wheel
wheeled
wipe
work
working