第1个回答 2011-12-26
Interesting question!
以下说法我觉得有点靠谱:
A canyon is a narrow chasm with steep cliff walls, cut into the earth by running water; a gorge usually formed by the down-cutting of a river in a dry area where there is insufficient rainfall to erode the sides.
A valley is an elongated lowland between ranges of mountains, hills, or other uplands, often having a river or stream running along the bottom; also an extensive area of land drained or irrigated by a river system.
Canyons have steep, cliff-like walls or sides, while valleys have gently sloping sides.
也就是说从两岸山体的形状来判断是valley还是canyon,canyon两岸通常是陡峭的悬崖。本回答被提问者采纳