英文介绍北极熊四年级 The polar bear is a bear native largely within the Arctic Circle encompassing（围绕，包围；）the Arctic Ocean，its surrounding seas and surrounding land masses.It is the world‘s largest land carnivore（食肉动物）and also the largest bear. In its existent space，it is the topmost food chain.It has thick fat and hair to stay warm，its white appearance on white snow is good protective coloration，and it can on land and sea，so it can catch food in the arctic in this extremely harsh climate. 本文来源：https://www.wddqw.com/doc/776a543b5bfb770bf78a6529647d27284b733715.html