恐龙在人类出现的6000万能年前就已经生活在地球上,他们生活在地球各处.旭东恐龙和鸡一样大小,也有一些比大象大10倍,另一些甚至能飞.Many dinosaurs ate plants.Howere,some dinosaurs liked to eat meat.Dinosaurs lived on Earth for more than 150 million years.Then,suddenly,they all died out.Nobody knows why.Howere,we can learn about them from their fosdils.