English verb conjugation
COULD STITCH

Regular verb: stitch - stitched - stitched

Affirmation

Simple form	V-ing form
I could stitch you could stitch he could stitch we could stitch you could stitch they could stitch	I could be stitching you could be stitching he could be stitching we could be stitching you could be stitching they could be stitching
Perfect	V-ing perfect
I could have stitched you could have stitched he could have stitched we could have stitched you could have stitched they could have stitched	I could have been stitching you could have been stitching he could have been stitching we could have been stitching you could have been stitching they could have been stitching

Negation

Simple form	V-ing form
I couldn't stitch you couldn't stitch he couldn't stitch we couldn't stitch you couldn't stitch they couldn't stitch	I couldn't be stitching you couldn't be stitching he couldn't be stitching we couldn't be stitching you couldn't be stitching they couldn't be stitching
Perfect	V-ing perfect
I couldn't have stitched you couldn't have stitched he couldn't have stitched we couldn't have stitched you couldn't have stitched they couldn't have stitched	I couldn't have been stitching you couldn't have been stitching he couldn't have been stitching we couldn't have been stitching you couldn't have been stitching they couldn't have been stitching

Interrogative form

Simple form	V-ing form
could I stitch? could you stitch? could he stitch? could we stitch? could you stitch? could they stitch?	could I be stitching? could you be stitching? could he be stitching? could we be stitching? could you be stitching? could they be stitching?
Perfect	V-ing perfect
could I have stitched? could you have stitched? could he have stitched? could we have stitched? could you have stitched? could they have stitched?	could I have been stitching? could you have been stitching? could he have been stitching? could we have been stitching? could you have been stitching? could they have been stitching?

Interro-negative form

Simple form	V-ing form
couldn't I stitch? couldn't you stitch? couldn't he stitch? couldn't we stitch? couldn't you stitch? couldn't they stitch?	couldn't I be stitching? couldn't you be stitching? couldn't he be stitching? couldn't we be stitching? couldn't you be stitching? couldn't they be stitching?
Perfect	V-ing perfect
couldn't I have stitched? couldn't you have stitched? couldn't he have stitched? couldn't we have stitched? couldn't you have stitched? couldn't they have stitched?	couldn't I have been stitching? couldn't you have been stitching? couldn't he have been stitching? couldn't we have been stitching? couldn't you have been stitching? couldn't they have been stitching?