英文關鍵字
boil
boiling
bubble
clay
dangerous
fumarole
gas
geology
geothermal
gray
grey
ground
heat
hole
hot
liquid
mud
muddy
natural
nature
outdoor
pool
shadow
steam
thermal
volcanic
英文關鍵字
boil
boiling
bubble
clay
dangerous
fumarole
gas
geology
geothermal
gray
grey
ground
heat
hole
hot
liquid
mud
muddy
natural
nature
outdoor
pool
shadow
steam
thermal
volcanic