The noun "sleep" can be both countable and uncountable.
Meaning: a natural state of rest
Example sentence: Fish and reptiles also need regular periods of sleep.
Meaning: a particular period of sleep
Example sentence: If I wake up too early in the morning, I have a short sleep after lunch.
Test your understanding:
- Whenever the kids don't get some sleep in the afternoon, they get upset.
- If grandma doesn't have a sleep in the afternoon, she gets grumpy.