1.The Earth is laced with thousands of rivers.
Rivers are channels of water that flow towards the sea. They allow the rain that falls on the land to drain away. Rivers also provide people and animals with drinking water and a place to wash, swim, and fish. A waterfall is a place where a river flows over a rocky ledge and pours down to a lower level.
2.The world's longest river is the Nile, in Africa.
It starts in the area near Lake Victoria and flows north to Egypt, where it opens into the Mediterranean Sea. The journey covers nearly 6700 kilometers and about 3470 cubic meters of water flows out of the Nile every second. The Nile provides water, a transport route, and fishing for millions of people. If it wasn't for the Nile, the civilization of ancient Egypt could not have existed.
3.Although the Nile is the longest river, the Amazon is the biggest.
The Amazon flows from west to east across South America and empties into the Atlantic Ocean. It carries 58 times as much water as the Nile, and about 200,000 cubic meters flow out of it each second. In some places, the Amazon is an amazing 60 kilometers wide.
V This aerial photo of the River Amazon shows how it twists and loops as it flows through the Amazon rainforest in South America. V
4.Angel Falls in Venezuela is the world's highest waterfall, spilling over a drop 979 meters high.
It flows off the side of a very high, flat-topped mountain. Although it's the world's highest waterfall, it's not the biggest. Many waterfalls are much wider and carry more water - including Niagara Falls in North America and Victoria Falls in Africa.
V At Angel Falls, the world's highest waterfall, the water spreads out into a misty spray as it plunges down the cliff. V
5.Rivers can cut through solid rock.
Over thousands of years, as a river flows it wears away the rock around it. If the stone is quite soft, the river can carve a deep, steep-sided valley, or gorge. The Grand Canyon in Arizona, USA, is a massive gorge cut by the Colorado River. It is about 450 kilometers long, and in areas, it is up to 29 kilometers wide and 1.8 kilometers deep.
V Part of the Grand Canyon, with the Colorado River visible at the bottom of a deep gorge. V
地球上有数千条河流。
河流是向海流动的水渠。他们允许落在地上的雨水流走。河流还为人和动物提供饮用水和洗涤，游泳和捕鱼的地方。瀑布是一条河流流过岩石的地方，向下倾斜。
世界上最长的河是非洲的尼罗河。
它从维多利亚湖附近的地区开始，向北流向埃及，在那里通往地中海。旅程涵盖近6700公里，每秒约有3470立方米的水流出尼罗河。尼罗河为数百万人提供水，运输路线和捕鱼。如果不是尼罗河，古埃及的文明就不可能存在。
虽然尼罗河是最长的河流，但亚马逊河是最大的。
亚马逊从西向东流向南美洲，并进入大西洋。它运载着尼罗河的水量的58倍，每秒流出约20万立方米。在某些地方，亚马逊是一个惊人的60公里宽。
V亚马逊溪流的这张空中照片显示了它流经南美亚马逊雨林时的扭曲和循环。 V
4.委内瑞拉的安格尔瀑布是世界上最高的瀑布，高达979米。
它从一个非常高，平顶山的一边流出。虽然它是世界上最高的瀑布，但它并不是最大的瀑布。许多瀑布都比较宽阔，并且携带更多的水 - 包括北美的尼亚加拉大瀑布和非洲的维多利亚瀑布。
V在世界最高的瀑布天使瀑布，当瀑布下降时，水分散入雾霭中。 V
河流可以穿透坚实的岩石。
几千年来，随着河流的流逝，它围绕着它周围的岩石。如果石头很软，那河可以雕刻一个深陡的山谷或峡谷。美国亚利桑那州的大峡谷是由科罗拉多河切割的大型峡谷。长约450公里，区域宽29公里，深1.8公里。
V大峡谷的一部分，科罗拉多河可见于深峡谷的底部。 V