could tack
Regular verb: tack - tacked- tacked

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could tack
you could tack
she could tack
we could tack
you could tack
they could tack 	I could be tacking
you could be tacking
she could be tacking
we could be tacking
you could be tacking
they could be tacking	I could have tacked
you could have tacked
she could have tacked
we could have tacked
you could have tacked
they could have tacked	I could have been tacking
you could have been tacking
she could have been tacking
we could have been tacking
you could have been tacking
they could have been tacking	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't tack
you couldn't tack
she couldn't tack
we couldn't tack
you couldn't tack
they couldn't tack 	I couldn't be tacking
you couldn't be tacking
she couldn't be tacking
we couldn't be tacking
you couldn't be tacking
they couldn't be tacking	I couldn't have tacked
you couldn't have tacked
she couldn't have tacked
we couldn't have tacked
you couldn't have tacked
they couldn't have tacked	I couldn't have been tacking
you couldn't have been tacking
she couldn't have been tacking
we couldn't have been tacking
you couldn't have been tacking
they couldn't have been tacking	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I tack?
could you tack?
could she tack?
could we tack?
could you tack?
could they tack? 	could I be tacking?
could you be tacking?
could she be tacking?
could we be tacking?
could you be tacking?
could they be tacking? 	could I have tacked?
could you have tacked?
could she have tacked?
could we have tacked?
could you have tacked?
could they have tacked? 	could I have been tacking?
could you have been tacking?
could she have been tacking?
could we have been tacking?
could you have been tacking?
could they have been tacking? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I tack?
couldn't you tack?
couldn't she tack?
couldn't we tack?
couldn't you tack?
couldn't they tack? 	couldn't I be tacking?
couldn't you be tacking?
couldn't she be tacking?
couldn't we be tacking?
couldn't you be tacking?
couldn't they be tacking? 	couldn't I have tacked?
couldn't you have tacked?
couldn't she have tacked?
couldn't we have tacked?
couldn't you have tacked?
couldn't they have tacked? 	couldn't I have been tacking?
couldn't you have been tacking?
couldn't she have been tacking?
couldn't we have been tacking?
couldn't you have been tacking?
couldn't they have been tacking?