The document discusses the simple past tense in English. It provides rules for forming the past tense of regular and irregular verbs. For regular verbs, the past tense is formed by adding "-ed" or "-d" to the base verb. Irregular verbs have unique past tense forms that must be memorized. The simple past can be used to talk about completed actions that occurred at a specific time in the past or habitual actions that took place in the past but are not ongoing. Examples are provided to illustrate affirmative, negative, and interrogative sentences in the simple past tense.