could vestibule
Regular verb: vestibule - vestibuled- vestibuled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could vestibule
you could vestibule
he could vestibule
we could vestibule
you could vestibule
they could vestibule 	I could be vestibuling
you could be vestibuling
he could be vestibuling
we could be vestibuling
you could be vestibuling
they could be vestibuling	I could have vestibuled
you could have vestibuled
he could have vestibuled
we could have vestibuled
you could have vestibuled
they could have vestibuled	I could have been vestibuling
you could have been vestibuling
he could have been vestibuling
we could have been vestibuling
you could have been vestibuling
they could have been vestibuling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't vestibule
you couldn't vestibule
he couldn't vestibule
we couldn't vestibule
you couldn't vestibule
they couldn't vestibule 	I couldn't be vestibuling
you couldn't be vestibuling
he couldn't be vestibuling
we couldn't be vestibuling
you couldn't be vestibuling
they couldn't be vestibuling	I couldn't have vestibuled
you couldn't have vestibuled
he couldn't have vestibuled
we couldn't have vestibuled
you couldn't have vestibuled
they couldn't have vestibuled	I couldn't have been vestibuling
you couldn't have been vestibuling
he couldn't have been vestibuling
we couldn't have been vestibuling
you couldn't have been vestibuling
they couldn't have been vestibuling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I vestibule?
could you vestibule?
could he vestibule?
could we vestibule?
could you vestibule?
could they vestibule? 	could I be vestibuling?
could you be vestibuling?
could he be vestibuling?
could we be vestibuling?
could you be vestibuling?
could they be vestibuling? 	could I have vestibuled?
could you have vestibuled?
could he have vestibuled?
could we have vestibuled?
could you have vestibuled?
could they have vestibuled? 	could I have been vestibuling?
could you have been vestibuling?
could he have been vestibuling?
could we have been vestibuling?
could you have been vestibuling?
could they have been vestibuling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I vestibule?
couldn't you vestibule?
couldn't he vestibule?
couldn't we vestibule?
couldn't you vestibule?
couldn't they vestibule? 	couldn't I be vestibuling?
couldn't you be vestibuling?
couldn't he be vestibuling?
couldn't we be vestibuling?
couldn't you be vestibuling?
couldn't they be vestibuling? 	couldn't I have vestibuled?
couldn't you have vestibuled?
couldn't he have vestibuled?
couldn't we have vestibuled?
couldn't you have vestibuled?
couldn't they have vestibuled? 	couldn't I have been vestibuling?
couldn't you have been vestibuling?
couldn't he have been vestibuling?
couldn't we have been vestibuling?
couldn't you have been vestibuling?
couldn't they have been vestibuling?