Let's Go Rock Collecting

Let's Go Rock Collecting

让我们去收集石头吧

People collect all kinds of things. They collect coins, stamps, baseball cards, shells, toys, bottles, pictures, and cats. Some people collect things that are very old-the older the better.

人们收集各种各样的东西。他们收集硬币、邮票、棒球卡、贝壳、玩具、瓶子、图画和猫。有些人收集非常古老的东西——越古老越好。

The oldest things you can collect are rocks. Most of them are millions and millions of years old. Most kinds of rocks are easy to find. But some, like diamonds and emeralds, are rare. That's why they are valuable.

你能收集的最古老的东西是石头。它们中的大多数都有数百万年的历史。大多数岩石都很容易找到。但有些宝石，如钻石和祖母绿，是罕见的。这就是为什么它们是有价值的。

Rocks cover the whole earth. No matter where you live, you live on rock. There is rock under city streets and country farms. And there is rock under every ocean, lake, and river.

岩石覆盖了整个地球。无论你住在哪里，你都住在岩石上。 城市街道和乡村农场下面有岩石。 在每一片海洋、湖泊和河流的下面都有岩石。

The Romans built roads out of rocks. The roads are still used today. Thing made with rocks last and last.

罗马人用岩石筑路。这些路至今仍在使用。用石头做的东西，经久不衰。

The rocks that make up the surface of the earth are called the earth's crust. Most of the crust is made of igneous rock. Igneous means made by heat. Inside the earth it is very hot--hot enough to melt rock. The melted rock is called magma. Sometimes the magma pushes through cracks in the crust. When magma comes to the surface, it is called lava. The lava cools and becomes very hard. It becomes igneous rock. Most of the earth's igneous rock comes from volcanoes on the seafloor.

构成地球表面的岩石称为地壳。地壳的大部分是由火成岩构成的。火成岩是指由热产生的。 地球内部非常热，热到足以融化岩石。熔化的岩石被称为岩浆。 有时岩浆会穿过地壳的裂缝。当岩浆到达地表时，它被称为熔岩。熔岩冷却后变得非常坚硬。它变成火成岩。地球上大部分的火成岩来自海底的火山。