(part of) the very large area of land in North Asia, North America, and northern Europe where, because it is cold, trees do not grow and ground below the surface is permanently frozen

Reindeer roam the tundra in large herds. 大群大群的驯鹿在苔原上徜徉。

Few plants grow in tundra regions. 苔原地区很少有植物生长。