This document provides information about relative clauses, including how they are used and formed. Relative clauses add information about a person or thing already mentioned to identify or distinguish them. They combine information into one sentence without repeating words. To form a relative clause, the information to identify what is being referred to comes first, followed by the relative pronoun (who, which, that, whose) and additional identifying information. The relative pronoun takes the role of the person or thing in the additional information.