English verb conjugation
COULD NITRIFY

Regular verb: nitrify - nitrified - nitrified

Affirmation

Simple form	V-ing form
I could nitrify you could nitrify he could nitrify we could nitrify you could nitrify they could nitrify	I could be nitrifying you could be nitrifying he could be nitrifying we could be nitrifying you could be nitrifying they could be nitrifying
Perfect	V-ing perfect
I could have nitrified you could have nitrified he could have nitrified we could have nitrified you could have nitrified they could have nitrified	I could have been nitrifying you could have been nitrifying he could have been nitrifying we could have been nitrifying you could have been nitrifying they could have been nitrifying

Negation

Simple form	V-ing form
I could not nitrify you could not nitrify he could not nitrify we could not nitrify you could not nitrify they could not nitrify	I could not be nitrifying you could not be nitrifying he could not be nitrifying we could not be nitrifying you could not be nitrifying they could not be nitrifying
Perfect	V-ing perfect
I could not have nitrified you could not have nitrified he could not have nitrified we could not have nitrified you could not have nitrified they could not have nitrified	I could not have been nitrifying you could not have been nitrifying he could not have been nitrifying we could not have been nitrifying you could not have been nitrifying they could not have been nitrifying

Interrogative form

Simple form	V-ing form
could I nitrify? could you nitrify? could he nitrify? could we nitrify? could you nitrify? could they nitrify?	could I be nitrifying? could you be nitrifying? could he be nitrifying? could we be nitrifying? could you be nitrifying? could they be nitrifying?
Perfect	V-ing perfect
could I have nitrified? could you have nitrified? could he have nitrified? could we have nitrified? could you have nitrified? could they have nitrified?	could I have been nitrifying? could you have been nitrifying? could he have been nitrifying? could we have been nitrifying? could you have been nitrifying? could they have been nitrifying?

Interro-negative form

Simple form	V-ing form
could I not nitrify? could you not nitrify? could he not nitrify? could we not nitrify? could you not nitrify? could they not nitrify?	could I not be nitrifying? could you not be nitrifying? could he not be nitrifying? could we not be nitrifying? could you not be nitrifying? could they not be nitrifying?
Perfect	V-ing perfect
could I not have nitrified? could you not have nitrified? could he not have nitrified? could we not have nitrified? could you not have nitrified? could they not have nitrified?	could I not have been nitrifying? could you not have been nitrifying? could he not have been nitrifying? could we not have been nitrifying? could you not have been nitrifying? could they not have been nitrifying?