英文關鍵字
tubes
industry
smoke
pipe
factory
pollution
one
sky
steam
chimney
environment
gas
fumes
smog
tower
technology
chemical
toxic
fog
substance
air
danger
industrial
chemistry
condensation
vapor
blue
urban
equipment
red
英文關鍵字
tubes
industry
smoke
pipe
factory
pollution
one
sky
steam
chimney
environment
gas
fumes
smog
tower
technology
chemical
toxic
fog
substance
air
danger
industrial
chemistry
condensation
vapor
blue
urban
equipment
red