First of all let us consider the earth (that is to say, the world) as a planet revolving round the sun. The earth is one of mine planets which move in orbit round the sun. These nine planets, together with the sun, make up what is called our solar system. How this wonderful system started and what kept it working with such wonderful accuracy is largely a mystery but astronomers tell us that it is only one of millions of similar systems is space, and one of the smallest.
The stars which we see glittering in the sky on a dark and cloudless night are almost certainly the suns of other solar systems more or less like our own, but they are so far away in space that it is unlikely that we shall ever get to know very much about them. About our own solar system, however, we are learning more every day.
Before the American and Russian astronauts made their thrilling journeys into outer space it was difficult for us to realise what our earth looked like from hundreds of thousands of miles away, but the photographs which the astronauts were able to take show us the earth in space looking not very different from what the moon looks like when we look at it from the earth. The earth is, however, very different from the moon, which the American astronauts have found to be without life or vegetation, whereas our earth is very much alive in every respect. The moon, by the way , is called a satellite because it goes round our earth as well as round the sun. In other words, it goes round the sun with our earth.
The surface of our earth is covered by masses of land and larger areas of water. Let us consider the water areas first. The total water area is about three times as large as the land area. The very large separate areas of water are called "oceans" and the lesser areas are called "seas."
In most of the oceans and seas some of the water is found to be flowing in a particular direction - that is to say, from one part towards another part of the ocean or sea concerned. The water which is flowing in this manner is said to be moving as a "current." There are many thousands of currents in the waters of the oceans and seas, but only certain of the stronger and better marked currents are specially named and or great importance. These currents are important because they affect the climate of the land areas close to where they flow and also because they carry large quantities of microscopic animal and vegetable life which forms a large part of the food for fishes.
The nature and characteristics of the surface of the land areas of the earth vary a great deal from area to area and from place to place. The surface of some areas consists largely of high mountains and deep valleys whilst, in other areas, most of the surface consists of plains. If one made a journey over the Continents one would find every kind of surface including mountain ranges, plains, plateaux, deserts, tropical forestlands and empty areas covered permanently by ice and snow.
When thinking and learning about the world we should not forget that our world is the home of a very great many different people - peoples with different colored skins, living very different lives and having very different ideas about a great many important things such as religion, government, education and social behavior.
The circumstances under which different people live make a great difference between the way in which they live and the way in which we live, and it ought to be our business to try to understand those different circumstances so that we can better understand people of other lands. Above all, we should avoid deciding what we think about people different from ourselves without first having learned a great deal about them and the kind of lives they have to live. It is true to say that the more we learn about other people, the better we understand their ideas and, as a rule, the better we like those people themselves.
首先讓我們把地球看作是圍繞太陽運行的一顆行星。地球是沿軌道圍繞太陽運行的九大行星之一。這九大行星和太陽一起組成了所謂的我們的太陽系。這個奇妙的星系是怎樣開始的，什麼使它保持精確地運行，這是一個很大的迷。但是天文學家告訴我們太陽系只是太空裏幾百萬個相似的星系中的一個而且是最小的一個。
在漆黑的夜空，我們看到的閃爍的星星幾乎肯定是其它太陽系中有些類似我們星系中的恆星。但是它們在太空中距離我們如此遙遠以至於我們不可能對其瞭解太多。然而對於我們的太陽系，每天我們都會了解到更多東西。
在美國和俄羅斯宇航員進行激動人心的太空旅行之前，我們很難認識到從數十萬英里以外的地方看地球會是什麼樣子。但是宇航員們能夠拍到的'照片爲我們展示出在太空中地球看上去和我們在地球上看到的月亮沒有什麼大的不同。然而，地球和月亮確有很大不同，這就是美國宇航員所發現的月球上沒有生命和植物。而我們地球的各個地方都有生機。順便說一下，月亮被稱爲衛星，是因爲它圍繞着我們地地球盍同時圍繞太陽運轉。換句話說，隨着地球圍繞太陽運行。
我們地球表面覆蓋着一塊塊的陸地和更大面積的水域。讓我們首先考慮一下水域，其總面積大約是陸地面積的三倍。很大的隔開的水域稱爲"洋"，小一些的水域稱爲"海"。
在大部分海洋裏，人們發現一些水是沿着特有的方向流動---這就是說，從海洋的一個區域流向另一區域以這種方式流動的水叫做"海流"。在海洋的水域裏有成千上萬條海流，但只有幾條較強和較顯着的海流被專門命名。這些海流的重要，是因爲它們影響着流經水域的陸地的氣候，並攜帶大量的微生物、植物，而這些卻是魚類的大部分食品。
地球不同區域的陸地表面自然特徵區別很大。一些區域的地表由大量的高山和深谷組成，而其它區域，大部分地表卻由平原組成。如果一個人做一次大陸旅行，他會發現各種各樣的地貌，包括山區、平原、高原、沙漠、熱帶雨林和永久性冰雪覆蓋的空曠無人區。
當我們想象和了解這個世界時，我們不應忘記我們的世界是許多不同種類人居住的家園--他們有不同的膚色，過着極不相同的生活，對諸如宗教、政府、教育和社交行爲等許多重要事情持有極爲不同的觀點。
不同民族的生活環境造就了他們和我們極爲不同的生活方式，我們應該做的是努力瞭解他們不同的生活環境以便更好地理解其它地區的人們。在沒有對他們及他們必須過的那種生活有相當多的認識前，我們應當避免對他們有先入爲主的看法。確實我們瞭解別人越多，我們越能理解他們的觀點，通常我們就會更喜歡那些人。
