This document discusses the present perfect simple and present perfect continuous tenses in English. The present perfect simple is used to describe life experiences, events that have already happened or not happened yet, connections between past and present, durations of time, and amounts. The present perfect continuous emphasizes actions that started in the past and continue in the present, repeated actions, and recently finished actions. Both tenses can be used with phrases like "how long" but the continuous is preferred for shorter or temporary actions. The simple form focuses on the result of an action while the continuous form focuses on the duration.