听力原文： The Eskimos need a great many different things to survive. To make a snow house they need a special knife, shaped something like a cutlass, to cut the snow blocks. For the bed platform. they need layers of heavy skins and furs and poles and brush to lay underneath. They need a deerskin blanket to cover the whole family at night. Then they need a set of short poles to make a frame. over the lamp for hanging the pot and for drying clothes. Flint and pyrite are needed to strike a spark to light the fire, and a special moss is needed to make wicks for the lamp. Then people need bone picks to take the hot meat out of the stew pot and cups to drink the hot soup. For melting snow or fresh water ice for drinking, they keep skin buckets on the platform. near a lamp. For a window in the house, they need a clear sheet of fresh water ice.
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A. They need layers of skins.
B. They need a great many poles.
C. They need a special knife.
D. They need many deerskin blankets.