A LOT VS A LOT OF

A lot	A lot of	Lots of
It’s like very often or very much (usually used at the end of a sentence)	A large amount of people or things (Formal)	A large amount of people or things ( Informal)
I ate a lot  She drank a lot We have a lot in common	A lot of people like apples She drank a lot of coffee	You have lots of time   She drank lots of coffee

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