This document provides instruction and examples for forming sentences in the past tense in English. It explains that the past simple is formed using "did" plus the base verb form, and does not change for subject ("he", "she", "it"). Examples are given for positive, negative, interrogative, and short answer forms of common verbs like "walk", "play", and "cook". A series of exercises follows for the reader to practice forming sentences in the past tense based on given prompts.