The noun "youth" can be both countable and uncountable.
Meaning: the time in someone's life when they're young
Example sentence: My cousin did lots of exciting things during his youth, but then he became a tax consultant.
Meaning: a young man
Example sentence: Youths in brightly-coloured shirts chased a ball on a field to impress the young females of their tribe.
Test your understanding:
- Most of the youths were sitting inside playing computer games.
- I spent most of my youth sitting inside playing computer games.