The French- (Thanks guys)

How did the French help aid the Americans in the last significant battle of the American Revolution; the Battle of Yorktown?

I will talk a little bit about the Americans before the french enter (ex: disease, discouraged, etc.) I will also talk about what the french gave the Americans (ex: naval battle, ammunition, etc.) Finally, I'll talk about the battle of Yorktown- why that battle is important and what took place at the battle.