英文關鍵字
action
asphalt
bitumen
broom
brush
building
business
car
city
clean
cleaner
cleaning
cleanliness
cleanup
detail
dirt
environment
equipment
garbage
giant
gravel
highway
industrial
industry
inspection
labor
machine
mud
old
outdoor
purify
road
rubbish
sand
service
street
sweep
sweeper
sweeping
tractor
traffic
truck
urban
vehicle
weather
wheeled
work