Dinosaurs are large reptiles that roamed the earth thousands of years ago. They mysteriously died out so no one knows for sure exactly how many kinds there were or what they looked like. Skeletons which have been found show us different kinds of teeth so scientists believe that some were meat eaters and some ate plants.
恐龙是几千年前生存在地球上的大型爬行动物。它们离奇地灭绝，没有人确切地知道究竟有多少种恐龙以及它们的模样。已发现的骸骨向我们展示多种不同类的牙齿，据此科学家认定，有些恐龙食肉而有些恐龙食草。
Paleontologists are scientists who study old fossils and bones. They have dug up pieces of dinosaur bones, cleaned them and brought them to museums to try to piece together a whole dinosaur. Since dinosaur skin was sometimes pressed into mud, which then hardened, scientists can tell what dinosaur skin looked like.
古生物学家是研究的化石和骸骨的科学家。他们挖出了恐龙骨骼碎片，清洗后把它们带回博物馆，试图拼凑出一只完整的恐龙。由于恐龙的皮肤有时被压入泥中，随后硬化，所以科学家可以辨认恐龙的皮肤。
A dinosaur skeleton put together from bones which have been dug up gives much information about what dinosaurs ate, what they looked like and how they defended themselves. The type of teeth or beak they had tells us what they might have eaten. Horns show us how a particular dinosaur defended itself.
挖掘出来的骨头拼凑出的恐龙骨架揭示了恐龙吃什么、长什么样、如何保护自己等信息。牙齿和嘴的类型展示了它们可能的进食对象，而角展示了其特殊的防御方式。
Fossilized skeletons may also give us the entire picture of what a certain dinosaur looked like. After a dinosaur died, the skeleton remained and was quickly pressed into the rock by some force, such as water or other rock, and then hardened. This is how a fossil is created. Fossils are flat, not three-dimensional, like bones.
化石骨架展示了某种恐龙的外形。恐龙死后，骨架保存下来并被诸如水或其他岩石施加的外力迅速压入岩石然后硬化。这就是化石形成的方式。化石和骨头一样是平的而非立体的。
To date, over 300 types of dinosaurs have been named. Dinosaurs are divided into two main groups according to their hip bones. Some had hips arranged like a bird and some like a lizard. Scientists have named many dinosaurs. Some of the lizard-like dinosaurs are Tyrannosaurus Rex, often known as the T-Rex, who was a meat eater, and Diplodocus, who was a plant eater. All bird-hipped dinosaurs were plant eaters. Iguanodon, Triceratops and Stegosaurus are three of the most famous of this type.
迄今为止，已有超过300种的恐龙被命名。恐龙根据其髋骨分为两大类。有些髋骨构造如同鸟类，有的又如蜥蜴。科学家命名了很多恐龙。一些蜥蜴状的恐龙是霸王龙，经常被称为T-雷克斯，它是肉食性恐龙，而梁龙是草食性恐龙。所有的鸟臀目恐龙是食草恐龙。该类中最有名的三者属禽龙、三角龙、剑龙。
Tyrannosaurus was one of the largest dinosaurs. Compsognathus was the size of a turkey. The largest of all was a group called Sauropods. The huge Sauropod, Barosaurus, might have been able to reach the top of a five-story building.
霸王龙是最大的恐龙之一。美颌龙只有火鸡的大小。最大恐龙类群是蜥脚类恐龙。巨大的蜥脚恐龙和重龙可能高达一栋五层建筑。
Sauropods were the biggest plant eaters. A Sauropod called Apatosaurus ate huge amounts of green plants every day. He didn't chew them but swallowed them along with stones that ground up the food in its stomach. Hadrosaurus had a beak like a duck and ripped up vegetation. He had more than 40 rows of teeth. Some plant eaters may have formed herds to defend themselves against the predatory meat eaters who had larger, sharper teeth.
蜥脚类恐龙是最大的食草动物。一种叫迷惑龙的蜥脚类恐龙每天进食大量的绿色植物。它没有咀嚼，连同石头一块儿吞咽，最后在胃内磨碎的食物。鸭嘴龙有着鸭子般的喙，它喜欢撕碎植被。它有40多排牙齿。一些食草动物成群活动从而保护自己免于体型更大、牙齿更加锋利肉食性动物的掠食。
The largest meat-eating dinosaur was the Giganotosaurus. Scientists think he may have weighed eight tons. Suchomimus ate fish and had a head like a crocodile. Baryonyx lived near water and also ate fish. His curved claw could spear fish. Tyrannosaurus was huge, but slow, and may have used his big head to butt against prey.
最大的肉食恐龙是南方巨兽龙。科学家们认为它可能重达8吨。它吃鱼，头部与鳄鱼头相似。重爪龙近水生活，也以鱼为食。它弯曲的爪子可以刺杀鱼。霸王龙很大，但速度缓慢，它可能用它的大脑袋撞击猎物。
In summary, dinosaurs are reptiles which lived on earth thousands of years ago. Some ate plants and some meat. Although they died out, scientists have learned much about them from bones and fossils.
恐龙是几千年前生活在地球上的爬行动物。它们有草食性的，也有肉食性的。虽然它们灭绝了，但科学家们已经通过其残骸和化石对他们有所了解了。