你晚上睡不着的时候会做什么(二)

Shondria, lives in Phoenix, AZ
Hello, I have major insomnia and a 15 month old daughter who seems to hate sleeping at night, and who's also stubborn and energetic, so you can one imagine how that works out with a boyfriend ( her step-father), who has to get sleep because he works all day, and there's no family members or friends that live anywhere near me. So I'm the only care taker for my little one, 24/7 non-stop, I've tried warm milk, a nice hot relaxing bath, I've even tried meditation, non of it worked out so my Dr. Prescribed me lunesta, adivan, trazidone, at separate times to see which one works and trazidone and lunesta worked, if you want to try something more natural, try melatonin, its a 100% natural hormone and this is how it works. Your body has its own internal clock that controls your natural cycle of sleeping and waking hours. In part, your body clock controls how much melatonin your body makes. Normally, melatonin levels begin to rise in the mid- to late evening, remain high for most of the nighthealthier then drop in the early morning hours. Natural melatonin levels slowly drop with age. Some older adults make very small amounts of it or none at all. Melatonin supplements are sometimes used to treat jet lag or sleep problems (insomnia). Scientists are also looking at other good uses for melatonin, such as:
Treating seasonal affective disorder (SAD).
Helping to control sleep patterns for people who work night shifts.
Preventing or reducing problems with sleeping and confusion after surgery.
Reducing chronic cluster headaches.You can buy melatonin supplements without a prescxtion at health food stores, drugstores, and online.
I hope that it helps you, it works great for me. I started using it because the other pills slowly started having side effects. I really like melatonin because its healthier and has little to no side effects, for me the only side effect a bit of tiredness in the morning for the first couple of days.


你好，我有严重的失眠症，我有一个15个月大的女儿，她似乎讨厌在晚上睡觉，而且她也很固执，精力充沛，所以你可以想象一下，和一个男朋友（她的继父）在一起是怎样的，他不得不睡觉，因为他整天都在工作，没有家人或朋友住在我身边。所以我是我孩子的唯一看护人，全天候无间断，我试过温牛奶，一个很好的放松方式：洗热水澡，我甚至试过冥想，但没有成功，所以我的医生给我开了lunesta，adivan，trazidone，在不同的时间看哪一个有效，trazidone和lunesta有效，如果你想尝试更自然的东西，试试褪黑素，它是一种100%天然激素，这就是它的工作原理：人的身体有自己的内部时钟，控制着你的睡眠和清醒时间的自然循环。在某种程度上，你的生物钟控制着你身体产生多少褪黑激素。通常情况下，褪黑激素水平在晚上中后期开始升高，在晚上大部分时间保持在较高水平，然后在清晨下降。而且褪黑素水平随着年龄的增长缓慢下降。一些老年人只摄入很少或根本不摄入。褪黑素补充剂有时用于治疗时差或睡眠问题（失眠）。科学家们也在研究褪黑素的其他良好用途，例如：
治疗季节性情感障碍（SAD）。
帮助夜班人员控制睡眠模式。
预防或减少手术后的睡眠和混沌问题。
减少慢性丛集性头痛。你可以在保健食品店、药店和网上购买褪黑素补充剂，无需处方。
我希望它能帮助你，它对我很有用。我开始使用它，因为其他药片慢慢开始有副作用。我真的很喜欢褪黑激素，因为它更健康，几乎没有副作用，对我来说，唯一的副作用是头几天早上有点累。

Michael Grandner, Director of U of Arizona Behavioral Sleep Medicine Clinical Program.
As a sleep scientist, I know a lot about how sleep works, and as a doctor I know what the current state of the science is in terms of how to get to sleep. Needless to say, I don't have a lot of sleep troubles. But I used to.
If you're having persistent trouble getting to sleep, you need to seek help. If it takes you more than a half hour to get to sleep at least 3 nights a week, you probably need more than a few tips. You've crossed the threshold into an insomnia disorder that probably requires treatment. The recommended approach is a non-medication approach called CBTI.
But if you don't have an insomnia disorder, some of the best things you can do are:
1. Don't spend excessive amounts of time in bed. This can lead to worse insomnia later. If you can't sleep, get out of bed.
2. Keep as regular a schedule as you can and keep a routine at night. This will help train your body and brain when to sleep.
3. Give yourself enough time to wind down at night. If your thoughts start taking over in bed, it means you didn't give yourself enough time to wind down and deal with those thoughts before getting into bed.
4. To quickly relax, diaphragmatic breathing and mindfulness meditation are great, if you've been able to get good at them through practice.


作为一名睡眠方向科学家，我知道很多关于睡眠的内在本质，作为一名医生，我知道关于如何入睡的科学现状。所以我是没有很多睡眠问题的。但我以前有。
如果你一直难以入睡，你需要寻求帮助。如果你一周至少有3晚需要半个多小时才入睡，你可能需要更多的提示。如果你已经进入失眠障碍的阶段，可能需要治疗。推荐的方法是称为CBTI的非药物治疗方法。
但是如果你没有失眠障碍，你可以做的最好的事情是：
1.不要在床上花费过多的时间。这可能会导致以后出现更严重的失眠。如果你睡不着，就起床。
2.尽可能有规律地安排日程，并在晚上保持规律作息。这将有助于训练你的身体和大脑何时睡觉。
3.在晚上给自己足够的时间放松一下。如果你的思想开始在床上占据主导地位，那就意味着你没有给自己足够的时间在上床之前放松下来处理这些思想。
4.要快速放松，膈肌呼吸和正念冥想是很好的，如果你能通过练习掌握它们的话。

Subhranil Ghoshal
Watching videos on YouTube. Often walkthroughs of games which I can’t play (my PC isn’t for gaming), or Cyanide & Happiness cartoons.
Watching videos of Demetri Martin on Facebook. He’s really good with jokes.
Reading answers on Quora or articles on Wikipedia.
Writing answers and/or managing spaces.
Reading books. Been reading All Quiet On The Western Front by Erich Maria Remarque as of now, preceded by the entire series of Animorphs.
Listening to music. Though listening to Slipknot is not recommended if you’re trying to get some sleep and are not feeling sleepy.
Thinking about things ranging from problems in mathematics/physics that I get stuck at to meeting my closest friend in real life (who doesn’t share a nation with me, however).
Trying to crack my knuckles over and over again.
Mumbling songs that I listen to over and over again.
Just listening to the clock ticking.
Counting how many hours of sleep I’m going to get.


在YouTube上观看视频。经常演练我不能玩的游戏（我的电脑不是用来玩游戏的），或者看《氰化物与幸福》动画片。
在Facebook上观看德米特里·马丁的视频，他很懂开玩笑。
阅读Quora上的答案或维基百科上的文章。
撰写答案和/或管理空间。
读书。从现在起，我一直在阅读埃里希·玛丽亚·雷马克的《西部前线的一切宁静》，之前是整个系列的《动物形态》。
听音乐。不过，如果你想睡一觉，又不觉得困，就不建议听Slipknot。
思考一些事情，从数学/物理方面的问题到遇到现实生活中最亲密的朋友（但他和我不是同一个国家）。
一次又一次地试图敲打我的指关节。
喃喃自语的歌曲，我听了一遍又一遍。
只是听着时钟滴答作响。
数着我能睡多少小时。

Dixie Conley, I love sleep, but have suffered from insomnia for many years
I can give you some suggestions, but to be quite frank, sometimes nothing works. Sometimes even the best sleeping pills and relaxation techniques and complete exhaustion just don’t work. I don’t know why this is, but it’s true.
Some things that have worked in the past:
Medication. Benadryl is readily available and has a soporific effect. Taking too many makes me itch, but that may just be me. You may be able to get your doctor to prescribe you something if you have chronic problems. I’ve also found cannabis to be useful in aiding sleep.
Exercise. Being physically tired is a great aid to sleep.
Meditation. Focus your mind on your breathing and return it gently to your breathing should your attention stray to anything worrisome or real. Should your attention stray to nonsense, however, let it stay. don’t seize onto them.
Story telling. I tell myself stories that have nothing to do with me or my circumstances. My mother likes to imagine what she’d pack if she was stranded on a desert island. Getting lost in the imagination can be a direct pathway to sleep.
Visualization and relaxation exercises, such as filling the body with heat, progression relaxation of the muscles, letting go of one’s worries. There are too many to recount here.
Breathing machine. If you snore, you may have sleep apnea. See your doctor to get tested. I still suffer from insomnia, but it happens a lot less now that I’m using my CPAP.
I’ve heard that not eating or drinking for an hour before you go to bed can help, but I’ve never paid attention to that myself. Could be worth a try.


我可以给你一些建议，但坦率地说，有时什么方法都不管用。有时候，即使是最好的安眠药、放松技巧和彻底的疲惫也不起作用。我不知道为什么，但这是真的。
一些在过去行之有效的方法:
药物治疗。苯海拉明很容易获得，有催眠作用。服用太多会让我发痒，但这可能只是我的问题。如果你有慢性疾病，你可以让你的医生给你开一些药。我还发现大麻有助于睡眠。
锻炼。身体疲劳对睡眠很有帮助。
冥想。将你的注意力集中在你的呼吸上，当你的注意力偏离到任何令人担忧的或真实的事情上时，将注意力轻轻地集中到你的呼吸上。然而，如果你的注意力转开了，那就让它留在那里吧，不要去管它们。
讲故事。我给自己讲的故事与我和我的处境无关。我妈妈喜欢想象如果她被困在荒岛上会带些什么。沉浸在想象中可能是入睡的直接途径。
想象和放松练习，比如让身体充满热量，逐步放松肌肉，释放忧虑。这里有太多的东西，无法一一列举。
呼吸机。如果你打鼾，你可能有睡眠呼吸暂停症状。去找医生检查一下。我仍然饱受失眠之苦，但现在我使用了CPAP，这种情况少了很多。
我听说睡觉前一小时不吃不喝会有所帮助，但我自己从来没有注意过。也许值得一试。
原创翻译：龙腾网 http://www.ltaaa.cn 转载请注明出处

Per Wickstrom, works at Chief Executive Officers
Some recommendations for insomnia:
· Take a walk. An extremely therapeutic action. Do not underestimate the power of a good walk. When you walk, look around at things in your surroundings. Do this for a while and you’re likely to go through a period of exhaustion. Do not stop there but keep going. Eventually, you’ll feel more awake, but it won’t be the jittery, nervous type. You should feel alx but calm, and sleep better.
· Exercise.This goes along with the walk but more focused on getting your cardiovascular system into action. People with desk jobs who drive to and from work – or work from home – tend to not get anywhere near the needed exercise. If you cannot sleep after a work-out, try it in the morning or early evening.
· Lay off the caffeine and sugar. Many are addicted to coffee or worse, “energy” drinks that contain questionable chemicals. Sugar is omnipresent. Try an organic superfood blast in the morning to kick start the day. By evening you should feel tired for the right reasons.
· Eat right. Our diets can be severely lacking in real nutrition, where the body is in a sort of shock. It simply isn’t functioning properly. Diet is of course a whole subject in itself, but you can start with common sense and skip the fast food, heavy starch intake and foods high in chemicals and additives. Try organic for a while and see how you feel.
· Drink lots of water. More people are dehydrated than is generally realized.
· Tryptophan.You’ve probably heard that this amino acid naturally occurs in turkey and is a reason you feel tired after Thanksgiving dinner. This is probably true Try a tryptophan supplement.
· Calcium and magnesium. You can get a powdered form and make a hot drink out of it. It calms your joints and relaxes the body.
· Write down your incomplete tasks. A lot of people that can’t sleep are stressed out about all the incomplete jobs they have floating around. Try writing them ALL down. Leave no stone unturned – the small and the large tasks. Then start working on them one at a time and getting them DONE. Your head may stop spinning around as you lay in bed.
Those are a few suggestions that have worked for me. Good luck!


针对失眠的一些建议:
散步：一种极具治疗作用的行为。不要低估散步的力量，当你走路的时候，看看周围的事物。这样做一段时间，你可能会经历一段精疲力竭的时期。不要停在那里，要继续前进。最终，你会感到更加清醒，但不会是那种紧张不安的状态。你应该感到警觉而平静，并且睡得更好。
锻炼：这与散步一起进行，但更侧重于让你的心血管系统发挥作用。在办公室工作的人开车上下班，或者在家工作，往往根本无法进行必要的锻炼。如果你在锻炼后睡不着，试着在早上或傍晚的时候睡觉。
戒掉咖啡因和糖：许多人对咖啡上瘾，甚至对含有可疑化学物质的“能量”饮料上瘾。糖是无所不在的。早上尝试一下有机食物，开始新的一天。到了晚上，你会因为正确的原因而感到疲劳。
正确的饮食：我们的饮食可能严重缺乏真正的营养，身体处于某种休克状态。它根本无法正常运转。饮食本身当然是一个完整的主题，但你可以从常识开始，跳过快餐，摄入大量淀粉和高化学物质和添加剂的食物。尝试一下有机食品，看看感觉如何。
多喝水：通常脱水的人比普通人有更多意识。
色氨酸：你可能听说过这种氨基酸在火鸡中自然存在，这就是你在感恩节晚餐后感到疲劳的原因。这可能是真的，试试色氨酸补充剂。
钙和镁：你可以拿一个粉状的产品，用它做一杯热饮。它能让你的关节平静下来，放松身体。
写下你没有完成的任务。很多人都睡不着觉，是因为手头上的工作都没做完而倍感压力。试着把它们都写下来，无论任务大小，都要千方百计去写。然后开始一个一个地完成它们，最后当你躺在床上时，你的头可能会停止转动。
这是一些对我有用的建议，好运！

Vladimir Vulchev
Eat your dinner at least 2:30, 3 hours before bed. That approach works best with most people when it comes to better sleep and more energetic and positive waking up on the next day.
Another tip is to go to bed early around 21:30 - 22:00 because it’s proven that the time frx between 22:00 and 24:00 equals to 4 hours of sleep after 24:00. In short, each hour of sleep in that period equals to 2 hours of sleep after midnight.
Avoid blue light exposure at least 2 hours before bedtime. That being said, laptops, tablets, phones and television. By doing that you will be able to go into the deeper phases of your sleep and recover your brain and energy systems way faster. Super important!


在睡觉前3个小时，至少也要睡前2:30吃晚饭。这种方法对大多数人来说是有效的，能够拥有更好的睡眠，第二天更积极得醒来，人也更有活力。
另一个建议是在21:30 - 22:00上床睡觉，因为事实证明，22:00到24:00之间的时间段的睡眠效果等于24:00之后的4个小时睡眠效果。简而言之，这段时间内的每一小时睡眠等于午夜之后的两小时睡眠。
至少在睡觉前2小时避免蓝光照射。也就是说，笔记本电脑、平板电脑、手机和电视都包括在内。通过这样做，你将能够进入更深的睡眠阶段，更快地恢复你的大脑和能量系统。（这一点）超级重要!
原创翻译：龙腾网 http://www.ltaaa.cn 转载请注明出处

Matthew Beech, Lifelong insomniac and expert on meds, regimes and other solutions
Let me count the ways… I have idiopathic insomnia: it is hereditary and I've had it my entire 46 years of life. Here are some tips:
Practice good “sleep ” essentially go to bed and get up the same time every day and never sleep in. Use your bedroom only for sleep and sex. Don't use phones or other screens before you try to sleep.
Avoid caffeine after 12pm and alcohol completely.
Keep a journal by your bed to write down anything that worries you as well as achievements for that day, plus things you are grateful for.
Get plenty of fresh air and exercise but no later than 6pm for a workout.
Always remember that 1–2 bad nights’ sleep won't kill you so you don't worry about it too much. I had 1.5 hours’ sleep last night and was at a hospital at 6am to see my second son born.
If you cannot sleep get up and do something for 20–30 mins. Don't lie there fretting about it. Try a glass of hot milk.
Don't eat a big meal before sleep but also don't go to bed hungry. Have a wholemeal sandwich, cereal or other high-fiber and/or serotonin-boosting food.
Try a white noise generator.
Google some mindfulness and meditation and breathing practices .
If all that fails seek medical attention and find the underlying cause. It may be physiological or psychological. Then there are medication and therapy options, but that’s a whole new subject.


让我数一数（有哪些方法），我患有特发性失眠症：这是遗传性的，我46年来一直患有这种病。以下是一些提示：
实践良好的“睡眠”。基本上每天都在同一时间睡觉和起床，从不睡懒觉。你的卧室只能用来睡觉和做爱。睡觉前不要看手机或其他屏幕。
晚上12点后避免咖啡因和酒精。
在床边写日记，写下任何让你担心的事情，以及那天的成就，还有你感激的事情。
获得充足的新鲜空气和锻炼，但不迟于下午6点进行锻炼。
永远记住，出现1到2个次睡眠不佳不会让你丧命，所以你不必太担心。我昨晚睡了1.5个小时，早上6点在医院看我的第二个儿子出生。
如果你睡不着，起床花20-30分钟做点什么。别躺在那里为这事烦恼。试试一杯热牛奶。
睡觉前不要吃大餐，也不要饿着肚子睡觉。吃全麦三明治、谷类食品或其他高纤维和/或血清素增强食品。
试试白噪声发生器。
搜索一些正念、冥想和呼吸练习。
如果所有这些都失败了，请就医并找到根本原因。它可能是生理上的或心理上的。还有药物和治疗方式的选择，但这是一个全新的课题。

Anna Nowak, A Polish living in Italy speaking both languages
Take a good look at the previous answers. I think most of them are useful.
I also agree with the ones who point out that a "healthy" ammount of workout/sports a day may benefit your night sleep.
The bed/matress and pillow quality are also very important.
You could also try listening to some relaxing music or try the brainwaves techiniques for deep sleep.
However, you should try to understand what the actual causes of your insomnia may be. Consulting your doctor and having some blood tests won't surely do you any wrong.
Sometimes - very often I would say - stress, depression or anxiety cause various sleep disorders. However the solution may be very simple in many cases. Long-term stress and depression cause a lot of psychological damages to you but they can also affect your physical condition as well. For example they may raise the consumption of magnesium by your system. If you don't introduce enough of this element into your organism, you will soon suffer from the deficiency of it with all of its unpleasant consequences.
For that reason you could start taking the Magnesium citrate supplement. It is water-soluble, natural, easily assimilated and brings a lot of benefits to your body.
Please, do your further research about magnesium and simply try it out (it is natural and considered to be safe and should not have side effects, however talk to your physician first). I'm sure you will soon notice the difference.
Good luck and good night!


仔细看看前面的答案。我认为大多数都是有用的。
我也同意一些人的观点，他们指出，每天进行“健康”的锻炼/运动可能有益于夜间睡眠。
床/床垫和枕头的质量也非常重要。
你也可以尝试听一些放松的音乐，或者尝试脑波技术来深度睡眠。
然而，你应该试着了解你失眠的真正原因可能是什么。向你的医生咨询并做一些血液检查，前提是肯定不会对你造成任何伤害。
有时我经常会说压力、抑郁或焦虑会导致各种睡眠障碍。然而，在许多情况下，解决方案可能非常简单。长期的压力和抑郁会对你造成很多心理伤害，但也会影响你的身体状况。例如，它们可能会增加你的系统对镁元素的消耗。如果你没有将足够的这种元素引入到你的机体中，你很快就会因缺乏这种元素而遭受所有不愉快的后果。
因此，你可以开始服用柠檬酸镁补充剂。它是水溶性的，天然的，易于吸收，给你的身体带来很多好处。
请对镁进行进一步研究，并简单试用（它是天然的，被认为是安全的，不应该有副作用，但是前提是先和你的医生谈谈）。我相信你很快就会注意到不同之处。
祝你好运，晚安！

Jon Waterman
There are two things I know which will help:
Practising meditation & “letting your hair down” approaches, I can say are two yet, differing ways of attacking this issue.
Firstly is meditation, the grounding effect.
Meditate & take up mindfulness.
Write down all the things which are troubling you.
Eat cereal & calcium.
Drink malt.
Listen to relaxing music which has no emotional connection.
Even watch TV as long as you dont become stimulated.
The second way, depending on whether you are in bed or whether you are contemplating sleep; is the “letting your hair down” approach.
Go to pub/bar where you know you will have a good time. Drink, play pool, play your favourite rock music, converse with others until you find a self minded person & have a discussion about all the things which are wrong with the world!
Other than a sore head the next day I believe this maybe as cathartic as the first way.
I ve tried to uate this paradox with a good friend who runs mindful classes & others who are experts & have yet to been given a clear answer.
And I now know why, because they either dont know or dare not advise such uncontrolled behaviour!


我知道有两件事会有帮助：
练习冥想和“放松你的头发”：我可以说这是解决这个问题的两种不同的方法。
首先是冥想，即根植效应。
冥想并接受正念。
把所有困扰你的事情都写下来。
吃谷物和钙。
喝麦芽酒。
听没有情感联系的让人放松的音乐。
即使是看电视也可以，只要你不因此感到兴奋就行。
第二种方法，取决于你是否是在床上还是是否在考虑睡觉；这是一种“放松你的头发”的方法。
去酒吧，在那里你会玩得很开心。喝酒，打台球，播放你最喜欢的摇滚乐，与他人交谈，和别人交谈，直到你找到一个有自我意识的人，并讨论世界上所有的错误！
除了第二天头痛之外，我相信这可能和第一种方法一样能起到宣泄作用。
我试着与一位开设正念课程的好朋友同其他专家一起评估这一悖论，但还没有得到明确的答案。
我现在知道为什么了，因为他们要么不知道，要么不敢建议这种不受控制的行为！

John L. Miller, Used to travel regularly 8 timezones. Survive on 5.5 hours a night.
It depends upon what I have to do the next day.
If I have a critical meeting, or if I've got serious jet lag (i.e. +/- 8 hours), I lay quietly in bed in the dark, relax my body with my eyes closed, and think a single word to keep my mind from wandering: for example "green. green. green..." 8 hours in bed awake like this isn't awesome, but it's worth a couple hours of sleep. Then the next night I sleep like a baby.
If I'm home, don't have anything especially important the next day, and can't sleep, then I get back up. Watch a movie, play games, surf the web. The important thing to me is not to be tossing and turning in bed. I go to bed whenever I get sleepy enough to, usually between 2 and 4 am.
In summary: if you have to be at your best the next day, make yourself rest even if you can't sleep.


这取决于我第二天要做什么。
如果我有一个重要的会议，或者我有严重的时差反应（即达到8个小时以上），我会在黑暗中静静地躺在床上，闭上眼睛放松身体，然后想一个词来让我的思维保持清醒：例如“绿色”。绿色绿色…“在床上睡8个小时即使像这样醒着并不可怕，但得睡上几个小时。然后第二天晚上我像婴儿一样睡觉。
如果我在家，第二天没有什么特别重要的事情，而且睡不着，那么我就会起来。看电影，玩游戏，上网。对我来说重要的是不要在床上辗转反侧。每当我困到可以睡觉的时候，我就上床睡觉，通常是在凌晨2点到4点之间。
总结：如果第二天你必须保持最佳状态，即使你无法入睡，也要让自己休息。

Al Griskaitis
If you can’t sleep because your mind is too busy then read on:
It’s common that if we are having difficulty sleeping that our subconscious will thrust our problems into consciousness. Our mind feels busy. We might have been falling asleep when our mind was distracted watching Netflix. Then we go to bed and thoughts start coming up.
If feels like a cloud of thoughts about a particular topic which we dwell on until we tangentialize into a different cloud of thoughts.
The thing to do is invest some energy before going to bed. Sit and think and try and crystallise each cloud of thoughts by defining each issue cloud in a clearly articulated way. Write it down. Then examine one at a time and decide if it’s solvable or not. And if it’s solvable determine what the next legitimate step might be taken “the next action” and make a plan to do that and set a realistic date/time to address it. If it’s not solvable, declare that the issue is “not solvable”.
Ideally, we would solve the solvable problems- but at bed time that’s highly unlikely; nor can we can enact any solution then. The best we can do was come up with “the next action” for a solvable problem and set a deadline.


如果你因为太忙而无法入睡，请继续阅读：
如果我们睡眠困难，我们的潜意识会将我们的问题推到意识中，这是很常见的。我们的头脑感到忙碌。当我们的注意力被Netflix分散时，我们可能已经睡着了。然后我们上床睡觉，开始思考。
如果感觉像是一团关于某个特定主题的思想云，我们一直在关注它，直到我们切向另一团思想。
要做的是在睡觉前投入一些精力。坐下来思考，通过以清晰的方式定义每个问题云，尝试并具体化每个思想云。写下来，然后挨个检查，再决定它是否可解。如果可以解决，确定下一个合法步骤可能是“下一个行动”，并制定一个这样做的计划，并设定一个现实的日期/时间来解决它。如果无法解决，则声明该问题“无法解决”。
理想情况下，我们将解决可解决的问题——但在睡觉时间，这是极不可能的；届时，我们也无法制定任何解决方案。我们所能做的就是为一个可解决的问题提出“下一步行动”，并设定一个最后期限。