The perfect aspect is expressed with a form of the auxiliary "have" together with the past participle of the verb. Thus the present perfect is "have written" or "has written", and the past perfect (pluperfect) is "had written". The perfect can combine with the progressive aspect (see above) to produce the present perfect progressive (continuous) "have/has been writing" and the past perfect progressive (continuous) "had been writing". There is a perfect infinitive "(to) have written" and a perfect progressive infinitive "(to) have been writing", and corresponding present participle/gerund forms "having written" and "having been writing". A perfect subjunctive ("have written") is also sometimes used. Future and conditional perfect forms are given below.