英語翻譯
How water shapes the earth
Water changes the face of the Earth as it movesthrough the great water cycle.Water wears down mountains,carves valleys,andcuts deep canyons (峽谷).It also builds deltas (三角洲) and straightens (弄直)coastlines.
During precipitation,some water falls on highlandsand mountains.The force of gravity pulls the water downhill.As the waterflows to lower levels,it erodes (侵蝕) thesoil and rocks.In this way,after many thousands of years,mountains are worndown.The water that runs off the land during precipitation cuts smallchannels.The larger channels drain into still larger ones,until finally thewater empties into the main stream that runs to the sea.The water carries tothe sea the materials it has eroded from the land.
Some of the precipitationthat falls is captured in mountain glaciers.As the glaciers slide downmountain sides,they cut the mountains into sharp and jagged (犬牙交錯的)peaks.The ocean also changes the face of the land.As waves pound (拍打)against the shore,they cut away land and leave steep cliffs (陡崖) .