The difference between less and fewer is actually really easy!
Use less with things that you can’t count:
There is less violence in the world today.
Less time is wasted on silly things.
He’s got less money than he had a year ago.
Use fewer with things that you can count:
Strong verbs are easier to read and use fewer words.
Fewer and fewer people know how to use this correctly.
And the most famous:
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