英文關鍵字
bag
boundary
dam
disaster
fence
flow
heap
levee
marsh
preparation
protection
retaining
river
sack
sand
sandbag
slow
stack
wall
water
英文關鍵字
bag
boundary
dam
disaster
fence
flow
heap
levee
marsh
preparation
protection
retaining
river
sack
sand
sandbag
slow
stack
wall
water