英文關鍵字
air
atmosphere
belch
belching
billowing
blue
carbon
catastrophe
chemical
chimney
chimneys
climate
cloud
coal
damage
danger
dioxide
dirty
ecological
ecology
emission
energy
environment
environmental
exhaust
factory
fuel
fume
gas
global
heat
industrial
industry
manufacturing
modern
ozone
pipe
plant
pollute
polluting
pollution
power
several
sky
smog
smoke
smokestack
smoking
station
steam
tower
toxic
two
twol
warming
waste