Difference between A lot and Lots of

[Guram]

Could you tell me please, what the difference between adjectives A lot and Lots of is?
And second question; Is this indirect question written corectly?
Thank you in advance.

[Mister Micawber]

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You can write 'tell me what the difference is between A and B' or 'tell me what the difference between A and B is'.

There is little or no difference between 'a lot (of)' and 'lots (of)' -- other than when used to mean a specific unit of area or merchandise. In the sense of 'much/many', perhaps 'lots' occurs more often before countable plural nouns:

There are lots / a lot of people in the lobby.
There is lots / a lot of money on the table.

Or perhaps it doesn't.

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