英文關鍵字
air
asia
atmosphere
boy
catastrophe
chemical
chimneys
choke
city
climate
contamination
cough
damage
danger
dirty
ecological
ecology
environment
environmental
face
factory
gas
gasp
guy
health
human
ill
industrial
industry
infection
kid
male
man
mask
one
outdoors
person
pipes
pollutant
pollution
protect
protection
protective
respirator
safety
sick
smoke
virus
warming
young