LESS VS. FEWER

 

Fewer and less can be confusing. Although both words are used as comparatives, they are used differently. 

FEWER

Fewer is used with countable nouns, things that can be counted or that normally have a plural such as friends, books, students..

Examples:

There are fewer customers theses days than last summer.

I should eat fewer candies.

There are fewer cookies in the box

LESS

Less is used with uncountable nouns, things that can't be counted or that don't normally have a plural such as money, bread, water...

Examples:

He has less money

There is less drinking water in the village because of the drought.

You should spend less time playing video games.

Less with numbers

Less is normally used with uncountable nouns and fewer with countable nouns. There are some exceptions; less can also be used with counting nouns that denote distance, amount, or time.

Examples:

Less than two weeks

Less than two miles.

Less than three kilos.

Revision activities

https://www.englishgrammar.org/less-and-fewer/

https://www.myenglishpages.com/english/grammar-exercise-fewer-less.php