The present perfect means that in the present time, the action has finished. In the past, it had finished, and in the future in English, it will have been finished by a certain time. In Tamil, the future perfect fits the translation "would have" instead.
In English, we form the Perfect by using the verb "have" conjugated in past, present or future, followed by the past participle (the "ed" form of the verb).
In Tamil, we form the Perfect by using the Adverb Participle (the Converbial) and the class 7 verb இரு (be).
The Adverb Participle covered here, is formed by taking the verb with its past stem and adding உ except for class 3 verbs which add இ.
- Past Perfect: I had bought it. நான் அதை வாங்கியிருந்தேன்.
- Present Perfect: I have bought it. நான் அதை வாங்கியிக்கிறேன்.
- Future Perfect: I would have bought it. நான் அதை வாங்கியிருப்பேன்.
The Perfect tense in Tamil can also have the meaning "be in the condition of" such as the phrase, "The door is closed" கதவு மூடியிருக்கிறது.