This document discusses the present perfect tense and when to use it. The present perfect is formed using have/has + past participle. It is used (1) when the time of an action is unimportant, (2) for actions that have occurred recently or so far, (3) for actions that have already occurred or not occurred yet, and (4) for actions that have occurred within a period of time that is not finished. The present perfect also connects actions to the present and is used to talk about the duration of an action over time.