The document defines and provides examples of the past continuous tense. The past continuous tense describes actions that began in the past and often continued for a short time after, such as "I was playing" or "She was cooking". It uses the structure of subject + was/were + verb+ing. The tense can be used to indicate an action occurring during a moment in the past, an unfinished action interrupted by another event, or something that continued before and after a particular time or action.