The document discusses the past continuous tense in English grammar. It provides examples of using the past continuous tense to describe actions that were happening at a specific time in the past, such as "I was playing badminton at this time yesterday." It also discusses using the past continuous tense along with the past simple tense to describe two simultaneous past actions, like "Sam hurt himself when he was jumping over the vaulting horse." Finally, it presents an example of using the past continuous tense to describe what different people were doing when a fire broke out.