Before we move to learn the structures, let’s have a look on some 3rd forms of verbs: Broken, Taken, Spoken, Drunk, Eaten, Cooked, Told, Bought, Brought, Painted, Gone and Come etc.
We use 3rd forms after may have, might have, could have, shall have, will have, would have, should have and must have. The other structurer ‘can have’ is not used in daily communication. I have categoried the structures below and explained their usage briefly.
This structure is used when you state the completion of a task based on doubt. For example “You must have done the work”. etc
This structure is used when the completion of an action is expressed in the past tense and also involves a doubt or possibility. For example “he might have told her”.
Use these three constructions for actions that will be completed in the present. Its detailed lessons will be further clarified in conditional clauses.
These phrases are used to express regret in the past. I should have come. I should have found it. I should have eaten. I shouldn’t have bothered her.
These structures are used for a prediction. Like your friend has done some mischief and got hit. And you do not know about his mischief, but you make a prediction from your guess. “You have been beaten because you must have done something wrong.”