What did keats contribute to English poetry?

His contributions were a lot of poetry. One of his most famous was called "Ode: Intimations of Immortality from Recollections of Early Childhood." Some of his most famous lines (from that poem) are:

Our birth is but a sleep and a forgetting:The Soul that rises with us, our life's Star,Hath had elsewhere its setting,And cometh from afar:

If you want to see more specifics, please visit the related link to his major works.