This document provides examples and explanations of the present perfect and past simple tenses in English. It begins with examples of sentences using the present perfect tense structure of subject + have/has + past participle. It then provides explanations of how the present perfect tense is used to describe unfinished past actions, past actions with present results, or indefinite time frames. It contrasts these uses with those of the past simple tense, such as finished past actions or those located within definite time frames. The document continues with exercises asking the reader to identify the correct tense to use in different sentence structures and contexts. It concludes by asking the reader to identify which tense is required in several example sentences.