英文關鍵字
air
blue
business
chemical
chimney
damage
dioxide
energy
factory
fumes
gas
industrial
industry
nature
pollution
refinery
sky
smog
smoke
steam
tower
winter
英文關鍵字
air
blue
business
chemical
chimney
damage
dioxide
energy
factory
fumes
gas
industrial
industry
nature
pollution
refinery
sky
smog
smoke
steam
tower
winter