The document discusses the difference between the present perfect and present perfect continuous tenses. The present perfect is used to describe completed actions with results in the present, while the present perfect continuous describes unfinished or ongoing actions that have begun in the past and continue in the present. Some verbs like "live", "work", and "study" can be used with either tense with little difference in meaning. Certain time expressions like "for" and "since" are used with both tenses, while others like "lately" and "recently" are only used with the present perfect continuous. Examples are provided to illustrate the differences.