英文關鍵字
abstract
background
bamboo
banaras
benares
black
bubbles
chemical
coconut
concept
conservation
danger
dirt
dirty
eco
ecology
energy
environment
environmental
factory
float
floating
ganges
garbage
hygiene
illustration
india
industrial
industry
liquid
natural
nature
plant
polluted
pollution
recycle
recycling
river
sea
soapy
state
technology
toxic
unclean
varanasi
waste
water