The document discusses the uses and formation of the past continuous tense in English. It provides examples of actions that were happening at a specific time in the past to illustrate the past continuous. It then outlines the affirmative, negative, and interrogative forms of the past continuous, which involves using a form of "to be" in the past tense plus the verb ending in "-ing." Examples are also given of asking what someone was doing at a certain time in the past.