Original: Tension mounts, however, when Harry is mysteriously chosen by the Goblet of Fire to compete in the dangerous Triwizard Tournament, even though another Hogwarts champion, Cedric Diggory, has already been selected.
Simplified: Tension mounts, however, when Harry is mysteriously chosen by the Goblet of Fire to compete in the dangerous Triwizard Tournament, even though another Hogwarts champion, Cedric Diggory, was already selected.