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 cannot retroact you cannot retroact he cannot retroact we cannot retroact you cannot retroact they cannot retroact	I cannot be retroacting you cannot be retroacting he cannot be retroacting we cannot be retroacting you cannot be retroacting they cannot be retroacting
Perfect	V-ing perfect
I cannot have retroacted you cannot have retroacted he cannot have retroacted we cannot have retroacted you cannot have retroacted they cannot have retroacted	I cannot have been retroacting you cannot have been retroacting he cannot have been retroacting we cannot have been retroacting you cannot have been retroacting they cannot 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 I not retroact? can you not retroact? can he not retroact? can we not retroact? can you not retroact? can they not retroact?	can I not be retroacting? can you not be retroacting? can he not be retroacting? can we not be retroacting? can you not be retroacting? can they not be retroacting?
Perfect	V-ing perfect
can I not have retroacted? can you not have retroacted? can he not have retroacted? can we not have retroacted? can you not have retroacted? can they not have retroacted?	can I not have been retroacting? can you not have been retroacting? can he not have been retroacting? can we not have been retroacting? can you not have been retroacting? can they not have been retroacting?