英文關鍵字
movement
tow
current
hydrology
hydrogeology
rafting
frigid
low
temperature
early
spring
stone
rounded
abrasion
melt
runoff
erosion
transport
outdoors
rural
countryside
turbulent
turbulence
hydraulic
phenom
phenomenon
phenomena
strength
danger
dangerous
cross
crossing
impediment
barrier
natural
power
energy
hydrodynamic
rapid
rapidly
fluid
dynamics
model
modeling
physics
kayak
kayaking
sieve
obstacle
strainer