This is a common English expression that we use in English when we want to go to bed and sleep.
Normally because we are tired or it is just time to go to bed.
The meaning of this expression is: to go to bed.
- I hit the sack early last night so today I have a lot of energy. I need it because there are many things to do.
- Ok kids it is late. Time to hit the sack. It's way past your bedtime.
- What time did you hit the sack? You look tired and run down. Try to go to bed a bit earlier tonight.
So remember, you can use this expression to tell your friends that you are tired and want to go to bed.
Here's another English expression for you to learn.
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