Nocturnal animals sleep by day and hunt by night.

夜间活动的动物白天睡觉晚上猎食。

《牛津词典》

The nocturnal animals hide in underwater caves by day, then venture out at night, feeding on small fish, squid, and octopus.

这种夜行性动物白天时隐藏在水底洞穴里，晚上才出来冒险，它们以小鱼、乌贼和章鱼为食。

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Nocturnal animals such as bats and owls only come out at night.

夜行动物，如蝙蝠和猫头鹰只在夜里才出来。

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Many of the trails are planked with wood, cutting down on the leech factor, and the lodge offers night wildlife drives to see nocturnal animals like the wide-eyed tarsier.

BBC: Malaysian Borneo on a single circuit

Catching sight of a wolf or a bear requires luck and patience, as they are nocturnal, elusive animals, but you may come across their tracks in the snow or the mud.

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