He was one of the first people to recognized that fossils were the castings and/or physical remains of life forms that had existed in the past.
(He; was; one of the first people to recognized that fossils were the castings and/or physical remains of life forms) (life forms; had existed; T:in the past)
He life forms
was had existed
one of the first people to recognized that fossils were the castings and/or physical remains of life forms
T:in the past