燃やす
aquatic
aqueous
block
boulder
brook
chunk
clean
clear
course
creek
erosion
fresh
geography
highland
hydrology
jet
let
limestone
low period
low water period
mountain
mountain river
nature
positive
power
real
rill
river
rivers
rivulet
rock
rubble
scarcity
science
sound
sounds
spring
stone
stream
time
tourism
travel
types
valley himalayas
water
waterfall
watery
wildlife
winter period