If headaches only occur at night, lack of fresh air and oxygen is often the cause.

如果头痛只发生在晚上，缺少新鲜空气和氧气常常是其原因。

《柯林斯英汉双解大词典》

I was the only person on deck at that time of night.

夜里那段时间只有我一个人在甲板上。

《牛津词典》

An elderly person may nap during the day and then sleep only five hours a night.

上了年纪的人白天会小睡一会儿，然后晚上只睡5个小时。

《柯林斯英汉双解大词典》

It is night time. And the only sound that can be heard is the long, lonely whistle coming from the train's engine.

VOA: special.2010.06.13

And, when he asks on their wedding night, she gives him an answer that only makes him more obsessed with the question.

当他在新婚之夜问这个问题时，海伦给了一个,只会让他更加对这个问题好奇的答案。

耶鲁公开课 - 1945年后的美国小说课程节选

I think for the past three months, I've only had five or six hours of sleep at night.

我觉得在过去三个月里，每晚我就睡5到6个小时。

I need 实战 - SpeakingMax英语口语达人

It is the only night race on the Formula One calendar.

CNN: FIA probes 'incidents' at F1 race last season

The race which is the only Formula One night race in the world and is set to continue annually until at least 2017 has emerged as one of the most glamorous Formula One events, broadcasting the impressive Singapore night skyline to millions globally.

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The boy, his two siblings and his mother were brought to Neverland by Jackson aides, where they spent most of February and March 2003, leaving once in the middle of the night, only to return later.

CNN: Jackson Case: Jurors acquit Jackson of all charges