英文關鍵字
air
asian
background
boy
catastrophe
chemical
chimneys
china
choke
climate
cough
damage
danger
dirty
disaster
ecological
ecology
environment
factory
filter
gas
gasp
global
guy
health
human
illness
industrial
industry
kid
male
man
mask
medical
outdoors
people
person
pipes
plant
pollution
protection
respirator
safety
sick
smoke
toxic
urban
virus
warming
young