关机的英语是 "shut down"。

关机这个词来源于英语动词 "shut",意思是"关闭",而 "down"是一个副词,表示"完全地"或"彻底地"。

例句:

Please shut down the computer when you finish using it. (请使用完电脑后关机。)
The power plant needs to shut down for maintenance. (发电厂需要关机进行维护。)
The website will be shut down permanently on December 31. (这个网站将于12月31日永久关闭。)

需要注意的是,"shut down"通常用于描述计算机或机器的关机,而不是人的关机。如果要表达人休息或睡觉的意思,可以使用 "go to sleep"或 "take a nap"。

例句:

I need to shut my eyes and take a nap before I continue working. (我需要闭上眼睛小睡一会儿才能继续工作。)
It's past midnight, I think it's time for me to shut down for the night. (已经过了午夜,我想是时候睡觉了。)