The document discusses different verb tenses and aspects in English, including how they are used to indicate the time or continuity of actions. It begins by explaining the simple present, past, and future tenses. It then discusses the progressive and perfect aspects. The progressive aspect uses "be + -ing" to indicate continuing actions, and has past, present, and future forms. The perfect aspect uses "have/has + past participle" to relate a past action to the present, and has past, present, and future forms. Finally, it discusses the perfect progressive aspect, which combines the ideas of continuation and completion over time.