English verb conjugation
COULD SHIRTTAIL

Regular verb: shirttail - shirttailed - shirttailed

Affirmation

Simple form	V-ing form
I could shirttail you could shirttail she could shirttail we could shirttail you could shirttail they could shirttail	I could be shirttailing you could be shirttailing she 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 she 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 she 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 couldn't shirttail you couldn't shirttail she couldn't shirttail we couldn't shirttail you couldn't shirttail they couldn't shirttail	I couldn't be shirttailing you couldn't be shirttailing she couldn't be shirttailing we couldn't be shirttailing you couldn't be shirttailing they couldn't be shirttailing
Perfect	V-ing perfect
I couldn't have shirttailed you couldn't have shirttailed she couldn't have shirttailed we couldn't have shirttailed you couldn't have shirttailed they couldn't have shirttailed	I couldn't have been shirttailing you couldn't have been shirttailing she couldn't have been shirttailing we couldn't have been shirttailing you couldn't have been shirttailing they couldn't have been shirttailing

Interrogative form

Simple form	V-ing form
could I shirttail? could you shirttail? could she shirttail? could we shirttail? could you shirttail? could they shirttail?	could I be shirttailing? could you be shirttailing? could she 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 she 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 she 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
couldn't I shirttail? couldn't you shirttail? couldn't she shirttail? couldn't we shirttail? couldn't you shirttail? couldn't they shirttail?	couldn't I be shirttailing? couldn't you be shirttailing? couldn't she be shirttailing? couldn't we be shirttailing? couldn't you be shirttailing? couldn't they be shirttailing?
Perfect	V-ing perfect
couldn't I have shirttailed? couldn't you have shirttailed? couldn't she have shirttailed? couldn't we have shirttailed? couldn't you have shirttailed? couldn't they have shirttailed?	couldn't I have been shirttailing? couldn't you have been shirttailing? couldn't she have been shirttailing? couldn't we have been shirttailing? couldn't you have been shirttailing? couldn't they have been shirttailing?