英文關鍵字
air
atmosphere
blue
building
carbon
chemical
chimney
chimneys
climate
cloud
coal
contamination
damage
dioxide
dirty
ecology
emission
energy
environment
environmental
exhaust
factory
fog
fuel
fumes
gas
global
industrial
industry
landscape
lonely
ozone
pipe
plant
polluting
pollution
power
problems
river
sky
smog
smoke
smokestack
stack
station
steam
sunset
technology
tower
toxic
vapor
warming
white