[Haskell-cafe] Monad for binary tree data structure

Hello, I built binary tree with: data Tree a = Empty                | Node a (Tree a) (Tree a)               deriving (Eq, Ord, Read, Show) How can i make Monad type class instance for this tree? And can i make it on not? i try: instance Monad Tree where     return x = Node x Empty Empty      Empty >>= f = Empty     (Node x Empty Empty) >>= f = f x  But i can't make (>>=) for Node x left right.  Thank you.