Although the Arctic looks lifeless, there are animals moving about. Caribou travel up and down feeding on the grass beneath the snow. The polar bears have a thick, waterproof coat. They eat birds' eggs, berries and dead whales. Walruses get shellfish from the ocean with their tusks. Seals have a layer of fat to keep them warm. They like to eat fish. The main idea of the paragraph is that although the【46】looks lifeless, there are a number of【47】there. Walruses get【48】from the ocean with their【49】. Seals have a【50】of fat to keep them warm.