(1)谷地，山谷 (stretch of lowland between ranges of mountains or hills)[C]：(town/city) nestle in a green～(城镇/市)隐现在绿色山谷中; (sb) live in/(river) flow along a beautiful～(某人)居住在美丽的峡谷/(河流)沿美丽的峡谷流淌;The～expands into a wide plain/has a river running through it. 这条峡谷扩展为一片广阔平原/有河流从中穿过。〖同〗basin，hollow，bottoms，gap;〖反〗mountain，mount，peak，cliff，ridge，hill;

(2)流域(land area drained by a river system)[C， 通常sing]：the～of the river 河的流域;the Nile/Yangtse/Mississippi V～尼罗河/长江/密西西比河流域;

【用法】两侧陡峭，既深又险的山谷为ravine或gorge(深谷，峡谷，沟壑);又小又陡的山谷为gully(溪谷，冲沟);非常大的峡谷为canyon(大峡谷);ghyll为新兴词， 意思与ravine同。