could backstitch
Regular verb: backstitch - backstitched- backstitched

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could backstitch
you could backstitch
he could backstitch
we could backstitch
you could backstitch
they could backstitch 	I could be backstitching
you could be backstitching
he could be backstitching
we could be backstitching
you could be backstitching
they could be backstitching	I could have backstitched
you could have backstitched
he could have backstitched
we could have backstitched
you could have backstitched
they could have backstitched	I could have been backstitching
you could have been backstitching
he could have been backstitching
we could have been backstitching
you could have been backstitching
they could have been backstitching	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't backstitch
you couldn't backstitch
he couldn't backstitch
we couldn't backstitch
you couldn't backstitch
they couldn't backstitch 	I couldn't be backstitching
you couldn't be backstitching
he couldn't be backstitching
we couldn't be backstitching
you couldn't be backstitching
they couldn't be backstitching	I couldn't have backstitched
you couldn't have backstitched
he couldn't have backstitched
we couldn't have backstitched
you couldn't have backstitched
they couldn't have backstitched	I couldn't have been backstitching
you couldn't have been backstitching
he couldn't have been backstitching
we couldn't have been backstitching
you couldn't have been backstitching
they couldn't have been backstitching	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I backstitch?
could you backstitch?
could he backstitch?
could we backstitch?
could you backstitch?
could they backstitch? 	could I be backstitching?
could you be backstitching?
could he be backstitching?
could we be backstitching?
could you be backstitching?
could they be backstitching? 	could I have backstitched?
could you have backstitched?
could he have backstitched?
could we have backstitched?
could you have backstitched?
could they have backstitched? 	could I have been backstitching?
could you have been backstitching?
could he have been backstitching?
could we have been backstitching?
could you have been backstitching?
could they have been backstitching? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I backstitch?
couldn't you backstitch?
couldn't he backstitch?
couldn't we backstitch?
couldn't you backstitch?
couldn't they backstitch? 	couldn't I be backstitching?
couldn't you be backstitching?
couldn't he be backstitching?
couldn't we be backstitching?
couldn't you be backstitching?
couldn't they be backstitching? 	couldn't I have backstitched?
couldn't you have backstitched?
couldn't he have backstitched?
couldn't we have backstitched?
couldn't you have backstitched?
couldn't they have backstitched? 	couldn't I have been backstitching?
couldn't you have been backstitching?
couldn't he have been backstitching?
couldn't we have been backstitching?
couldn't you have been backstitching?
couldn't they have been backstitching?