Individual dolphins also enter a deeper form of sleep, mostly at night.

个别海豚也会睡得较沉，特别是在夜间。

youdao

In captivity, the giraffe sleeps intermittently around 4.6 hours per day, mostly at night.

笼子里的长颈鹿每天大约会断断续续地睡4.6小时，大部分时间是在晚上。

youdao

They eat mostly at night.

VOA: special.2009.05.26

Cars batteries are a good match with wind power because they mostly charge at night, when people are sleeping, and wind tends to peak at night.

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Though seeing a newborn turtle make its way to the ocean is unlikely ('They mostly hatch at night, ' says Pakdin), swimmers may see a full-grown green turtle travel across the seabed.

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The thought ten years ago was that they would mostly be charged at night, filling in the valley of low off-peak demand, and thus allowing more kilowatt-hours to flow across the same infrastructure.

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