Beginning at adolescence, kids have what's called a delayed sleep phase, where they start sleep later and sleep later in the morning.

青春期伊始，孩子们会产生所谓的睡眠相位后移症，症状表现为入睡比平时晚，起床也比平时晚。

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I have a circadian rhythm disorder called delayed sleep phase syndrome.

我有昼夜节奏紊乱的问题，即睡眠相位后移综合症。

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