This document discusses three types of wish clauses: 1. Wishes about the present using "I wish/If only" + past simple tense. Examples given. 2. Wishes about the past using "I wish/If only" + past perfect tense. Examples given. 3. Wishes for requests/complaints using "I wish/If only" + subject + "would" + infinitive. Examples given. The document then provides a dialogue example using wish clauses where a character expresses regret over mistakes made in a past relationship and wishes to change the present and future.