No matter how tired we are, but it still need to continue for the next step.

i do not know what is the time to off my work, but the sky telling me, is the time to back home.

No matter how tired are you to getting more effort to your work. You still need to survive the next business day, but not necessarily very miserable. This is how you spend the day, in fact, is also efficient.

"When you're really tired, working is tough no matter what you do. That said, there are ways to help make the day easier and actually get things done. You're not going to feel bright and cheery, but you can avoid turning into a zombie. We've looked at quick fixes for feeling tired, but in this post we're going to examine what you can do to help yourself during the entire day. Essentially, your goal will be to give yourself extra energy and avoid behaviors that will make your exhaustion worse. With a little bit of effort you'll be able to avoid passing out."
(like https://lifehacker.com/5917644/how-to-survive-the-workday-when-youre-completely-exhausted/)

雨歇晚霞明，风调夜景清。月高微晕散，云薄细鳞生。露草百虫思，秋林千叶声。相望一步地，脉脉万重情。这是刘禹锡 【秋晚新晴夜月如练有怀乐天】