Pattern I : S + have/has + been + complement
Pattern II : S + have/has + Verb III + O/adverb

Present perfect is formed by combining have/has with the main verb’s past participle form:

I have arrived.

A negation is produced by inserting not after have/has:

I have not arrived.

Questions in present perfect are formulated by starting a sentence with have/has:

Has she arrived?


Past Perfect Tense is a kind of tense that is used to describe an action or an event that started in a certain time in the past and completed or finished till certain time in the past too; or past perfect tense is used to express an action or an event that had happened before the other event or action happened


The pattern :
(+) Subject + had+verb III+cmplement
(-) Subject + had not+ver III+complement
(?) Had + subject +verb III+complement


Example :
(+) We had eaten before they came
(-) They had not eaten before we came
(?) Had they eaten before we came?


Adverbs used :
from 1998 to 1999, once, twice, etc.


Past Future Tense is used to assert an action or an event that will happened before or at the other event happened at the past future.


Pattern I : S + would/should + have + been + complement
Pattern II : S + would/should + have + verb III + O/adverb


Present Future Tense is used to assert an action or an event that will happened or will finished at the definite time at the future.


Pattern I : S + (except I) + will/shall + have + been + complement
Pattern II : S + will/shall + have + Verb III + O/adverb