could vein
Regular verb: vein - veined- veined

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could vein
you could vein
he could vein
we could vein
you could vein
they could vein 	I could be veining
you could be veining
he could be veining
we could be veining
you could be veining
they could be veining	I could have veined
you could have veined
he could have veined
we could have veined
you could have veined
they could have veined	I could have been veining
you could have been veining
he could have been veining
we could have been veining
you could have been veining
they could have been veining	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't vein
you couldn't vein
he couldn't vein
we couldn't vein
you couldn't vein
they couldn't vein 	I couldn't be veining
you couldn't be veining
he couldn't be veining
we couldn't be veining
you couldn't be veining
they couldn't be veining	I couldn't have veined
you couldn't have veined
he couldn't have veined
we couldn't have veined
you couldn't have veined
they couldn't have veined	I couldn't have been veining
you couldn't have been veining
he couldn't have been veining
we couldn't have been veining
you couldn't have been veining
they couldn't have been veining	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I vein?
could you vein?
could he vein?
could we vein?
could you vein?
could they vein? 	could I be veining?
could you be veining?
could he be veining?
could we be veining?
could you be veining?
could they be veining? 	could I have veined?
could you have veined?
could he have veined?
could we have veined?
could you have veined?
could they have veined? 	could I have been veining?
could you have been veining?
could he have been veining?
could we have been veining?
could you have been veining?
could they have been veining? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I vein?
couldn't you vein?
couldn't he vein?
couldn't we vein?
couldn't you vein?
couldn't they vein? 	couldn't I be veining?
couldn't you be veining?
couldn't he be veining?
couldn't we be veining?
couldn't you be veining?
couldn't they be veining? 	couldn't I have veined?
couldn't you have veined?
couldn't he have veined?
couldn't we have veined?
couldn't you have veined?
couldn't they have veined? 	couldn't I have been veining?
couldn't you have been veining?
couldn't he have been veining?
couldn't we have been veining?
couldn't you have been veining?
couldn't they have been veining?