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来源:雅诚德英语网
Over the past two million years, colder glacial periods have alternated with warmer interglacial periods.
在过去的200万年里,寒冷的冰期与较暖和的间冰期交替出现。
Over the past two million years, colder glacial periods have alternated with warmer interglacial periods.
在过去的200万年里,寒冷的冰期与较暖和的间冰期交替出现。