機器
auto
background
blade
brush
business
car
city
clean
cleaning
concept
contamination
dust
equipment
industrial
industry
machinery
mechanic
mechanics
mechanism
mechanization
modern
modernization
municipal
roads
roadway
scraper
service
sidewalk
sidewalks
snow
street
sweeping
sweeps
system
technology
tools
urban
vehicle
washes
waste
weather
winter
work