This document provides information about the past perfect tense and used to. It explains that the past perfect tense uses the structure "subject + had + past participle" and is used to talk about something that happened before another action in the past. It provides examples of questions and negatives in the past perfect tense. It also discusses time words that are commonly used with the past perfect tense. Additionally, it explains that "used to" is used to talk about past habitual or continuous actions that are no longer true, and provides examples of its structure and use.