英文關鍵字
air
background
blue
chemical
chimney
city
climate
cloud
coal
construction
copter
dirty
dust
ecology
electric
electricity
energy
environment
factory
footprint
fuel
gas
global
heat
industrial
industry
infrastructure
manufacturing
nuclear
oil
pipe
plant
pollution
power
radioactive
refinery
sky
skyline
smog
smoke
stack
station
steam
structure
technology
tower
toxic
warming
white