This document provides instruction on using the simple past, present perfect, and present perfect progressive tenses in English. It begins with an advertisement for an experienced adventure travel guide who has been guiding trips in Colorado for 10 years. Various examples are then given to illustrate the appropriate uses of each tense. For the simple past, actions that were completed in the past are used. The present perfect and present perfect progressive describe actions that began in the past and continue to the present. Time expressions like "for" and "since" are also discussed. Exercises are included for the reader to practice identifying and using the different tenses.