We're a puritanical society when it comes to sleeping late in the morning. We equate having a lie-in to being a lazy good-for-nothing. Teenagers in particular suffer at the hands of such ignorant criticism.
在早晨睡懒觉这个问题上，我们的社会是一个极其严格的社会。我们将躺着与懒惰、无所事事划等号。尤其是青少年，他们更是承受着这种无知批评带来的痛苦。
The fact is, teens can no more bounce out of bed early in the morning than you can run 100m in 10 seconds.
事实上，青少年早晨不能早起和你无法在10秒钟内跑完100米是一样的性质。
We've known for some time that the teenage brain literally "deconstructs", meaning that brain connections are broken, brain rhythms are disrupted and brain centres don't function. Crucial among those lost functions is a broken body clock.
青少年的大脑以“解构”著称，也就是说他们的脑部连接断了、大脑节奏被打乱了、脑中心不起作用了。在这些丧失的功能中，最重要的一个就是生物钟被打乱了。
It's still a 24-hour clock but it's not in sync with day and night. This means teens don't want to go to sleep until after midnight and don't want to wake up until late morning.
生物钟还是24小时，但却没有和白天黑夜同步。这就意味着，青少年到了半夜才想上床睡觉，早晨直到睡过了头才想起床。

For virtually all adolescents, the secretion of melatonin (the body clock's sleeping pill) doesn't begin until about 11pm and continues until about 8am.
对几乎所有的青少年而言，褪黑激素（生物钟的安眠药）直到晚上11点左右才开始分泌，并一直持续到早晨8点左右。
This means that most teenagers simply can't fall asleep until this secretion begins, and find it impossible to wake up until the melatonin turns off.
也就是说，大多数的青少年要到褪黑激素开始分泌才能入睡、直到褪黑激素停止分泌才能醒来。
This fixed pattern of melatonin secretion in teens doesn't normalise until they're in their 20s.
直到20多岁，青少年这种固定的褪黑激素分泌模式才会开始正常。
So the unique sleep/wake pattern of teenagers is beyond their control.
所以这种独特的入睡/起床模式是青少年无法掌控的。
There are serious consequences if teens fail to get adequate sleep. Those who are sleep-deprived – defined as getting less than eight hours per night – are more likely to smoke, drink and take drugs.
若青少年未能获得充足睡眠，后果将十分严重。那些睡眠不足的青少年--定义是每晚睡眠时间少于8小时--更有可能吸烟、喝酒、嗑药。
With less than nine hours of sleep per night, depression among teens rises significantly.
由于每晚睡眠不足9小时，患抑郁症的青少年大幅增多。
Research shows around half of teenagers who sleep four hours or less per night feel sad and hopeless, compared to those who sleep longer.
研究表明，与睡眠更久的青少年相比，每晚只睡4个小时或更少时间的青少年中，有一半以上会感到难受、无助。
Teen car crashes, the primary cause of death for this age group, significantly decline when teens obtain more than eight hours of sleep per night.
车祸是青少年死亡的主要原因，当青少年每晚睡眠8小时以上时，车祸率会大大降低。