could prefab
Regular verb: prefab - prefabed- prefabed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could prefab
you could prefab
he could prefab
we could prefab
you could prefab
they could prefab 	I could be prefabing
you could be prefabing
he could be prefabing
we could be prefabing
you could be prefabing
they could be prefabing	I could have prefabed
you could have prefabed
he could have prefabed
we could have prefabed
you could have prefabed
they could have prefabed	I could have been prefabing
you could have been prefabing
he could have been prefabing
we could have been prefabing
you could have been prefabing
they could have been prefabing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't prefab
you couldn't prefab
he couldn't prefab
we couldn't prefab
you couldn't prefab
they couldn't prefab 	I couldn't be prefabing
you couldn't be prefabing
he couldn't be prefabing
we couldn't be prefabing
you couldn't be prefabing
they couldn't be prefabing	I couldn't have prefabed
you couldn't have prefabed
he couldn't have prefabed
we couldn't have prefabed
you couldn't have prefabed
they couldn't have prefabed	I couldn't have been prefabing
you couldn't have been prefabing
he couldn't have been prefabing
we couldn't have been prefabing
you couldn't have been prefabing
they couldn't have been prefabing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I prefab?
could you prefab?
could he prefab?
could we prefab?
could you prefab?
could they prefab? 	could I be prefabing?
could you be prefabing?
could he be prefabing?
could we be prefabing?
could you be prefabing?
could they be prefabing? 	could I have prefabed?
could you have prefabed?
could he have prefabed?
could we have prefabed?
could you have prefabed?
could they have prefabed? 	could I have been prefabing?
could you have been prefabing?
could he have been prefabing?
could we have been prefabing?
could you have been prefabing?
could they have been prefabing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I prefab?
couldn't you prefab?
couldn't he prefab?
couldn't we prefab?
couldn't you prefab?
couldn't they prefab? 	couldn't I be prefabing?
couldn't you be prefabing?
couldn't he be prefabing?
couldn't we be prefabing?
couldn't you be prefabing?
couldn't they be prefabing? 	couldn't I have prefabed?
couldn't you have prefabed?
couldn't he have prefabed?
couldn't we have prefabed?
couldn't you have prefabed?
couldn't they have prefabed? 	couldn't I have been prefabing?
couldn't you have been prefabing?
couldn't he have been prefabing?
couldn't we have been prefabing?
couldn't you have been prefabing?
couldn't they have been prefabing?