Present Perfect Tense:

We use this tense when we want to express a sentence with the verb have/ has (verbo haber). In this case the verb have/has (according with the pronoun) is used like the auxiliar verb and the principal verb used in this tense is the participle verb.

In the regular verbs the participle verb uses the ending -ED.
For Example: Travel- Traveled
                     Play- Played
                     Discover- Discovered

In the irregular verbs the participle verb change in sometimes all the word or sometimes a few letters.
For Example: Drink- Drank- Drunk
                     Think- Thought- Thought
                     Sleep- Slept- Slept

The forms of the present perfect tense: