The document discusses various uses of verb tenses in business writing, focusing on past tenses. It covers the past simple tense and how it is used to describe completed actions, definite moments in time, and past descriptions. It then covers the past continuous tense and how it emphasizes duration, creates context, describes repeated past events, planned events that did not occur, and makes polite requests. Finally, it discusses the past perfect tense and how it refers to the past of the past, can be continuous, and describes finished vs unfinished past activities.