English verb conjugation
COULD PREFAB

Regular verb: prefab - prefabed - prefabed

Affirmation

Simple form	V-ing form
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
Perfect	V-ing perfect
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
I could not prefab you could not prefab he could not prefab we could not prefab you could not prefab they could not prefab	I could not be prefabing you could not be prefabing he could not be prefabing we could not be prefabing you could not be prefabing they could not be prefabing
Perfect	V-ing perfect
I could not have prefabed you could not have prefabed he could not have prefabed we could not have prefabed you could not have prefabed they could not have prefabed	I could not have been prefabing you could not have been prefabing he could not have been prefabing we could not have been prefabing you could not have been prefabing they could not have been prefabing

Interrogative form

Simple form	V-ing form
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?
Perfect	V-ing perfect
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
could I not prefab? could you not prefab? could he not prefab? could we not prefab? could you not prefab? could they not prefab?	could I not be prefabing? could you not be prefabing? could he not be prefabing? could we not be prefabing? could you not be prefabing? could they not be prefabing?
Perfect	V-ing perfect
could I not have prefabed? could you not have prefabed? could he not have prefabed? could we not have prefabed? could you not have prefabed? could they not have prefabed?	could I not have been prefabing? could you not have been prefabing? could he not have been prefabing? could we not have been prefabing? could you not have been prefabing? could they not have been prefabing?