How and why did Motte and Bailey castles change to stone castles?

Because the wood which they were made of would rot and it was frequently being attacked with fire and the castles were burning down. They replaced the wood with stone and moved the castles if they needed to be in a better position.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.