Polar bears live mostly on sea ice, which they use as platform for hunting seals
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Polar bears live mostly on _____ sea ice, which they use as ___ platform for hunting seals.
A. a; a B. a; the C. 不填;a D. the; 不填
试题答案
C
解析:
sea ice 海冰, 是固定结构,不用冠词;platform平台,是可数名词。