English verb conjugation
COULD UNNAIL

Regular verb: unnail - unnailed - unnailed

Affirmation

Simple form	V-ing form
I could unnail you could unnail he could unnail we could unnail you could unnail they could unnail	I could be unnailing you could be unnailing he could be unnailing we could be unnailing you could be unnailing they could be unnailing
Perfect	V-ing perfect
I could have unnailed you could have unnailed he could have unnailed we could have unnailed you could have unnailed they could have unnailed	I could have been unnailing you could have been unnailing he could have been unnailing we could have been unnailing you could have been unnailing they could have been unnailing

Negation

Simple form	V-ing form
I could not unnail you could not unnail he could not unnail we could not unnail you could not unnail they could not unnail	I could not be unnailing you could not be unnailing he could not be unnailing we could not be unnailing you could not be unnailing they could not be unnailing
Perfect	V-ing perfect
I could not have unnailed you could not have unnailed he could not have unnailed we could not have unnailed you could not have unnailed they could not have unnailed	I could not have been unnailing you could not have been unnailing he could not have been unnailing we could not have been unnailing you could not have been unnailing they could not have been unnailing

Interrogative form

Simple form	V-ing form
could I unnail? could you unnail? could he unnail? could we unnail? could you unnail? could they unnail?	could I be unnailing? could you be unnailing? could he be unnailing? could we be unnailing? could you be unnailing? could they be unnailing?
Perfect	V-ing perfect
could I have unnailed? could you have unnailed? could he have unnailed? could we have unnailed? could you have unnailed? could they have unnailed?	could I have been unnailing? could you have been unnailing? could he have been unnailing? could we have been unnailing? could you have been unnailing? could they have been unnailing?

Interro-negative form

Simple form	V-ing form
could I not unnail? could you not unnail? could he not unnail? could we not unnail? could you not unnail? could they not unnail?	could I not be unnailing? could you not be unnailing? could he not be unnailing? could we not be unnailing? could you not be unnailing? could they not be unnailing?
Perfect	V-ing perfect
could I not have unnailed? could you not have unnailed? could he not have unnailed? could we not have unnailed? could you not have unnailed? could they not have unnailed?	could I not have been unnailing? could you not have been unnailing? could he not have been unnailing? could we not have been unnailing? could you not have been unnailing? could they not have been unnailing?