n. 流沙, 流沙区, 危险状态

Quicksand \Quick"sand`\, n.
Sand easily moved or readily yielding to pressure;
especially, a deep mass of loose or moving sand mixed with
water, sometimes found at the mouth of a river or along some
coasts, and very dangerous, from the difficulty of
extricating a person who begins sinking into it.

Life hath quicksands, -- Life hath snares!
--Longfellow.