English verb conjugation
CAN RETROACT

Regular verb: retroact - retroacted - retroacted

Affirmation

Simple form	V-ing form
I can retroact you can retroact he can retroact we can retroact you can retroact they can retroact	I can be retroacting you can be retroacting he can be retroacting we can be retroacting you can be retroacting they can be retroacting
Perfect	V-ing perfect
I can have retroacted you can have retroacted he can have retroacted we can have retroacted you can have retroacted they can have retroacted	I can have been retroacting you can have been retroacting he can have been retroacting we can have been retroacting you can have been retroacting they can have been retroacting

Negation

Simple form	V-ing form
I can't retroact you can't retroact he can't retroact we can't retroact you can't retroact they can't retroact	I can't be retroacting you can't be retroacting he can't be retroacting we can't be retroacting you can't be retroacting they can't be retroacting
Perfect	V-ing perfect
I can't have retroacted you can't have retroacted he can't have retroacted we can't have retroacted you can't have retroacted they can't have retroacted	I can't have been retroacting you can't have been retroacting he can't have been retroacting we can't have been retroacting you can't have been retroacting they can't have been retroacting

Interrogative form

Simple form	V-ing form
can I retroact? can you retroact? can he retroact? can we retroact? can you retroact? can they retroact?	can I be retroacting? can you be retroacting? can he be retroacting? can we be retroacting? can you be retroacting? can they be retroacting?
Perfect	V-ing perfect
can I have retroacted? can you have retroacted? can he have retroacted? can we have retroacted? can you have retroacted? can they have retroacted?	can I have been retroacting? can you have been retroacting? can he have been retroacting? can we have been retroacting? can you have been retroacting? can they have been retroacting?

Interro-negative form

Simple form	V-ing form
can't I retroact? can't you retroact? can't he retroact? can't we retroact? can't you retroact? can't they retroact?	can't I be retroacting? can't you be retroacting? can't he be retroacting? can't we be retroacting? can't you be retroacting? can't they be retroacting?
Perfect	V-ing perfect
can't I have retroacted? can't you have retroacted? can't he have retroacted? can't we have retroacted? can't you have retroacted? can't they have retroacted?	can't I have been retroacting? can't you have been retroacting? can't he have been retroacting? can't we have been retroacting? can't you have been retroacting? can't they have been retroacting?