This document provides examples and explanations of how to use various perfect tenses and time expressions in English to talk about past actions and experiences. It discusses using the present perfect tense to talk about actions that began in the past and continue to the present or have present results. It also covers using "since" and "for" to indicate when something started, and the expressions "ever", "already", "just", "yet", and asking "how long" to provide additional context about the timing or duration of events.