English verb conjugation
CAN RETESTIFY

Regular verb: retestify - retestified - retestified

Affirmation

Simple form	V-ing form
I can retestify you can retestify he can retestify we can retestify you can retestify they can retestify	I can be retestifying you can be retestifying he can be retestifying we can be retestifying you can be retestifying they can be retestifying
Perfect	V-ing perfect
I can have retestified you can have retestified he can have retestified we can have retestified you can have retestified they can have retestified	I can have been retestifying you can have been retestifying he can have been retestifying we can have been retestifying you can have been retestifying they can have been retestifying

Negation

Simple form	V-ing form
I can't retestify you can't retestify he can't retestify we can't retestify you can't retestify they can't retestify	I can't be retestifying you can't be retestifying he can't be retestifying we can't be retestifying you can't be retestifying they can't be retestifying
Perfect	V-ing perfect
I can't have retestified you can't have retestified he can't have retestified we can't have retestified you can't have retestified they can't have retestified	I can't have been retestifying you can't have been retestifying he can't have been retestifying we can't have been retestifying you can't have been retestifying they can't have been retestifying

Interrogative form

Simple form	V-ing form
can I retestify? can you retestify? can he retestify? can we retestify? can you retestify? can they retestify?	can I be retestifying? can you be retestifying? can he be retestifying? can we be retestifying? can you be retestifying? can they be retestifying?
Perfect	V-ing perfect
can I have retestified? can you have retestified? can he have retestified? can we have retestified? can you have retestified? can they have retestified?	can I have been retestifying? can you have been retestifying? can he have been retestifying? can we have been retestifying? can you have been retestifying? can they have been retestifying?

Interro-negative form

Simple form	V-ing form
can't I retestify? can't you retestify? can't he retestify? can't we retestify? can't you retestify? can't they retestify?	can't I be retestifying? can't you be retestifying? can't he be retestifying? can't we be retestifying? can't you be retestifying? can't they be retestifying?
Perfect	V-ing perfect
can't I have retestified? can't you have retestified? can't he have retestified? can't we have retestified? can't you have retestified? can't they have retestified?	can't I have been retestifying? can't you have been retestifying? can't he have been retestifying? can't we have been retestifying? can't you have been retestifying? can't they have been retestifying?