英文關鍵字
adult
air
boy
catastrophe
caucasian
chemical
chimneys
choke
city
climate
cough
crisis
danger
dangerous
disaster
earth
ecological
ecology
environment
factory
gas
gasp
global
guy
hazard
health
holding
human
industrial
industry
landscape
man
mask
measure
one
people
person
plant
pollution
protection
protective
rate
respirator
risk
safe
smoke
stack
warming
wearing
young