This document provides information about the present perfect continuous tense in English. It explains that the present perfect continuous describes an action that began in the past and continues in the present. It can be used with time expressions like "for" and "since" to indicate how long an action has been ongoing. Several examples are given to illustrate the difference between the present continuous and present perfect continuous. The document also discusses using the present perfect continuous with "how long" questions versus the simple present perfect.