Formal:
* 我要去睡觉了 (Wǒ yào qù shuìjiào le) - This literally translates to "I am going to go to sleep." This is a polite and formal way to say it.
* 我得去睡觉了 (Wǒ de qù shuìjiào le) - This means "I have to go to sleep." It emphasizes the necessity of going to sleep.
Informal:
* 我要睡了 (Wǒ yào shuì le) - This means "I'm going to sleep" and is a casual way to say it.
* 我该睡觉了 (Wǒ gāi shuìjiào le) - This means "I should go to sleep." It suggests you're tired and it's time to sleep.
Very informal:
* 睡觉了 (Shuìjiào le) - This is the most basic way to say it, meaning "sleep." It's often used among friends or family.
In addition to the above:
* If you are using a messaging app, you can also use a sleep emoji (😴).
The best option depends on the specific context and your relationship with the person you are speaking to.