This document provides an overview of the present perfect continuous tense in English. It explains that the present perfect continuous describes an action that began in the past and continues into the present. It can be used with time expressions like "for" or "since" to indicate how long an action has been ongoing. Common verbs used in the present perfect continuous include "be", "work", "wait", and "study". The document provides examples to illustrate the differences between the present continuous, present perfect, and present perfect continuous tenses.