How do you use 'a lot of ' and ' lots of ' in sentences?

"Wow, there was a lot of children at that picnic..."

It snows a lot in the winter.She has a lot of friends.Do you like a lot of syrup on your waffles?

I spend a lot of my free time on WikiAnswers.

I have to use the word a lot a lot because a lot is the word you ask for a lot. :)

I found a lot of worms in my back yard.