Expressions of quantity

A lot of Lots ofA lot

a lot of / lots ofa lot of and lots of have the same meaning: they both mean a large amount or number of people or things.They are both used before countable nouns and uncountable nouns:with countable nouns:A lot of people went to the game.Lots of people went to the game.with uncountable nouns:A lot of snow falls in winter.Lots of snow falls in winter.

a lota lot means very often or very much. It is used as an adverb. It often comes at the end of a sentence and never before a noun.I like basketball a lot.She's a lot happier now than she was.I don't go there a lot anymore.