早在近二亿年前的中生代三迭纪,地球上就出现了恐龙。在这以后的一亿几千万年间,恐龙繁荣兴盛,统治了整个地球。当时地上爬行的,水中游的,以至空中飞的都是恐龙。在地上爬行的恐龙之中最大的恐龙——梁龙,身体长达二十五米,有四、五层楼高。水中游的蛇颈龙和沧龙也长达十五米。就连空中飞的无尾飞龙也 As early as nearly 200 million years ago in the Mesozoic Triassic, dinosaurs appeared on Earth. Tens of millions of years later, dinosaurs flourished and ruled the entire earth. At that time, crawling on the ground, swimming in the water, and even flying in the air were all dinosaurs. The largest dinosaur among the dinosaurs crawling on the ground, Liang Long, has a body of 25 meters in length and four or five stories high. In the water, the plesiosaurs and dragons are also fifteen meters long. Even the flying tailless dragon is also