This document discusses the present perfect continuous tense in English. It is used to express present actions that started in the past and continue into the present, such as "He has been living in Rome since 1975." It also discusses the negative ("I haven't been working there for more than three") and interrogative ("How long have you been living in Paris?") forms. Keywords that indicate the present perfect continuous include "for," "how long," "since," "recently," and "long."