have + past participle 

The perfect aspect is expressed with the auxiliaryA helping verb used with main verbs to express mood, voice and tense. E.g.: I can't stand when I am disturbed. ("can", "am") have and the third form of the verbA part of speech that expresses an action or a state. E.g.: John seldom plays tennis. (past participle). Depending on the timeA concept which is related to our perception of reality; that part of existence which is measured in seconds, minutes, hours, days, weeks, etc. of the actionA general term expressing that somebody or something does something, we use the past (had), present (have, has), modal + infinitive (e.g. will have) or -ing (having) form of have.

The perfect aspect focusThe main or central point of attention or interest; what is emphasized. E.g.: All I wanna do is have some fun. ("all")es on the completion of an eventA general term expressing that somebody or something does something or that something happens. E.g.: An apple fell on Isaac’s head.. It expresses that the action had, has or will have been completeA concept, related to the perfect aspect, expressing that an action has finished. E.g.: He’s finished university.d by a particular point of timeA particular moment in time. E.g.: She came home at six. ("six") I was born in 1980. ("1980") . This point of time may be defined by a time expressionA word or group of words used in a particular situation. E.g.: Good morning, at six, on the sofa (by 5 o'clock) or a clauseA group of related words containing a subject and a verb. (by the time you get home, when I arrived).

Examples of the perfect aspect: 

I've lived here for ten years. (from 10 years ago until now)
By 5 o'clock he had finished the letter. (at some time before 5 o'clock)
When I arrived, they had alrady left. (at some time before I arrived)
Have you seen my new bike? (at any time up to now)
I will have done the ironing by the time you get home. (between now and when you get home)
He might have missed the train. (at some time before now)
Having taken the wrong turn, Geoffrey ended up in a dangerous suburb. (before he found himself in a dangerous suburb)

Diagrams

The continuous aspect
Aspects The perfect continuous "aspect"