It may come as no surprise that the verb is haber, which is translated as the auxiliary verb "to have." As an auxiliary verb, haber in Spanish and "to have" in English are used to form the perfect tenses.

No, they aren't called the perfect tenses because they're better than the others. But one meaning of "perfect," one we don't see very often today outside of literature, is "complete." The perfect verb tenses, then, refer to completed actions (although they aren't the only way of referring to completed actions).

Contrast two ways of referring to something that happened in the past: He salido ("I have left") and estaba saliendo ("I was leaving"). In the first instance, it is clear that the act described by the verb is completed; it's something that was over by a specific time. But in the second case, there is no indication in the second structure when it was completed; in fact, the act of leaving still could be occurring.

In both English and Spanish, the perfect tenses are formed by using a form of the verb haber/"to have" followed by the past participle (el participio in Spanish). In English, the participle typically is formed by adding "-ed" to verbs; the Spanish participle, which has origins related to the English participle, typically is formed by adding using the ending of -ado for -ar verbs and -ido for -er and -ir verbs.

The tense of the resulting verb depends on which tense of haber is used. Use the present tense of haber to create the present perfect tense, the future tense to create the future perfect tense, and so on.

Here are examples of the various tenses using haber salido ("to have left") in the first-person singular.

Note that the preterite perfect indicative tense isn't used in speech or much in modern writing. You're most likely to find it in literature.

Note also that when standing alone, the subjunctives forms are indistinguishable in English. In Spanish, the structure of the sentence, not how the verb is translated into English, will determine when the subjunctive is used. See the lessons on the subjunctive for more information on this verb mood.