There are lots of marine mammals such as whales and seals in the sea.

海洋里有许多诸如鲸鱼和海豹类的海生哺乳动物.

《简明英汉词典》

When marine mammals sleep and swim at once , they are in a state similar to napping.

当海洋哺乳动物一边睡觉一边游泳时, 它们处在与打瞌睡相似的状态.

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To avoid drowning during sleep, it is crucial that marine mammals retain control of their blowhole.

为避免在睡眠时溺水, 海洋哺乳动物保持对呼吸孔的控制至关重要.

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Peninsula Valdes in Patagonia is a site of global significance for the conservation of marine mammals.

位于巴塔哥尼亚地区的瓦尔德斯半岛是全球海洋哺乳动物资源的重点保护区.

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