... hotel) Punctuation Commas are not used in defining relative clauses. Relative pronouns The following relative pronouns are used in defining relative clauses: Person Thing Place Tim e Reason ... non-defining relative clauses. If the non- defining relative clause occurs in the middle of a sentence, a comma is put before the relative pronoun and at the end of the clause. If the non-defining relative ... in relative clause and appositive clause Appositive clauses look a lot like relative clauses, but they are fundamentally different in structure. Remember that a relative...