The document discusses two structures used to talk about what people say, think, know, etc.: a "that clause" structure and a "to infinitive clause" structure. It provides examples of how these structures are used with different verbs and tenses. The passive voice can be used with either structure. A variety of verbs representing speech, thought, or opinion are listed that can be used in these patterns, such as say, think, believe, expect, assume. Tense changes and negatives are also addressed.