An estuary is the wide part of a river where it meets the sea. The water there is mixed: not fully fresh, not fully salt. It often looks broad and quiet, and it rises and falls with the tide.

An estuary河口灣 is是 the wide part of a river河流變寬的那一段 where it meets the sea和海交會的地方 The water there那裡的水 is mixed是混合的 not fully fresh不完全是淡水 not fully salt也不完全是鹹水 It它 often looks broad and quiet通常看起來又寬又平靜 and it還 rises and falls with the tide隨著潮汐漲落

Birds, fish, and crabs like this mix, and ships may use it as a way into the land. People sometimes call any river mouth an estuary, but the real picture is this whole tidal stretch of mixed water, not a single line on a map.

Birds, fish, and crabs鳥、魚和螃蟹 like this mix喜歡這種混合的環境 and ships船 may use it as a way into the land也可能靠它進到內陸 People有些人 sometimes call any river mouth an estuary會把任何河口都叫estuary but但 the real picture真正的畫面 is是 this whole tidal stretch of mixed water這整片有潮汐、水混合的區域 not a single line on a map不是地圖上的一條線

It is also not the same as a delta. A delta is land the river builds by dropping mud in a fan; an estuary is water and shore where river and sea share the space. A river can have one, the other, or a bit of both.

It它 is also not the same as a delta也跟delta（三角洲）不一樣 A delta delta（三角洲） is是 land the river builds by dropping mud in a fan河流靠沉積泥沙堆出來的扇形陸地 an estuary estuary則 is是 water and shore where river and sea share the space河和海共用空間的水域和岸邊 A river一條河 can have可能有 one, the other, or a bit of both其中一種、另一種，或兩種都有一點

This is a geography word, and you will also hear it in news about ports, birds, and floods.

This這 is a geography word是一個地理用字 and you也 will also hear it會聽到它 in news about ports, birds, and floods在港口、鳥類和水災的新聞裡