This document discusses different verb tenses including present, present perfect, past, past perfect, future, and future perfect tenses. It explains that verb tenses indicate when an action occurred in relation to the present and can be used to discuss literature, make historical events seem current, express general truths, and show habitual actions. The present tense expresses current actions while the present perfect tense expresses indefinite past actions that may continue to the present. The past tense expresses completed past actions and the past perfect expresses actions completed before another past action.