Perfect (grammar)

The perfect tense or aspect (abbreviated PERF or PRF) is a verb form that indicates that an action or circumstance occurred earlier than the time under consideration, often focusing attention on the resulting state rather than on the occurrence itself. An example of a perfect construction is I have made dinner: although this gives information about a prior action (my making the dinner), the focus is likely to be on the present consequences of that action (the fact that the dinner is now ready). The word perfect in this sense means "completed" (from Latin perfectum, which is the perfect passive participle of the verb perficere "to complete").

In traditional Latin and Ancient Greek grammar, the perfect is a particular conjugated verb form considered to be one of the tenses. Modern analyses view the perfect constructions of these languages as combining elements of grammatical tense (such as time reference) and grammatical aspect. The Greek perfect contrasted with the aorist and the imperfect, and referred specifically to completed events with present consequences; its meaning was thus similar to that of the English construction "have/has (done something)". The Latin perfect contrasted only with the imperfect (used for past incomplete actions or states), and was thus used to mean both "have/has done something" and "did something" (the preterite use). Other related forms are the pluperfect, denoting an event prior to a past time of reference, and the future perfect, for an event prior to a future time of reference.

In the grammar of some modern languages, particularly of English, the perfect may be analyzed as an aspect that is independent of tense – the form that is traditionally just called the perfect ("I have done") is then called the present perfect, while the form traditionally called the pluperfect ("I had done") is called the past perfect. (There are also additional forms such as future perfect, conditional perfect, and so on.) The formation of the perfect in English, using forms of an auxiliary verb (have) together with the past participle of the main verb, is paralleled in a number of other modern European languages.

...
Wikipedia