English verb conjugation
COULD SHIRTTAIL

Regular verb: shirttail - shirttailed - shirttailed

Affirmation

Simple form	V-ing form
I could shirttail you could shirttail he could shirttail we could shirttail you could shirttail they could shirttail	I could be shirttailing you could be shirttailing he could be shirttailing we could be shirttailing you could be shirttailing they could be shirttailing
Perfect	V-ing perfect
I could have shirttailed you could have shirttailed he could have shirttailed we could have shirttailed you could have shirttailed they could have shirttailed	I could have been shirttailing you could have been shirttailing he could have been shirttailing we could have been shirttailing you could have been shirttailing they could have been shirttailing

Negation

Simple form	V-ing form
I could not shirttail you could not shirttail he could not shirttail we could not shirttail you could not shirttail they could not shirttail	I could not be shirttailing you could not be shirttailing he could not be shirttailing we could not be shirttailing you could not be shirttailing they could not be shirttailing
Perfect	V-ing perfect
I could not have shirttailed you could not have shirttailed he could not have shirttailed we could not have shirttailed you could not have shirttailed they could not have shirttailed	I could not have been shirttailing you could not have been shirttailing he could not have been shirttailing we could not have been shirttailing you could not have been shirttailing they could not have been shirttailing

Interrogative form

Simple form	V-ing form
could I shirttail? could you shirttail? could he shirttail? could we shirttail? could you shirttail? could they shirttail?	could I be shirttailing? could you be shirttailing? could he be shirttailing? could we be shirttailing? could you be shirttailing? could they be shirttailing?
Perfect	V-ing perfect
could I have shirttailed? could you have shirttailed? could he have shirttailed? could we have shirttailed? could you have shirttailed? could they have shirttailed?	could I have been shirttailing? could you have been shirttailing? could he have been shirttailing? could we have been shirttailing? could you have been shirttailing? could they have been shirttailing?

Interro-negative form

Simple form	V-ing form
could I not shirttail? could you not shirttail? could he not shirttail? could we not shirttail? could you not shirttail? could they not shirttail?	could I not be shirttailing? could you not be shirttailing? could he not be shirttailing? could we not be shirttailing? could you not be shirttailing? could they not be shirttailing?
Perfect	V-ing perfect
could I not have shirttailed? could you not have shirttailed? could he not have shirttailed? could we not have shirttailed? could you not have shirttailed? could they not have shirttailed?	could I not have been shirttailing? could you not have been shirttailing? could he not have been shirttailing? could we not have been shirttailing? could you not have been shirttailing? could they not have been shirttailing?