The document discusses the past simple tense in English. It provides examples of how to form the past simple by adding "-ed" to regular verbs or using irregular past forms. It also gives examples of affirmative, negative, and interrogative sentences. The document notes that the past simple is used to talk about things that happened at a specific time in the past or completed actions in the past. It lists common time expressions used with the past simple, such as "yesterday" or "last week."