Warning, this verb may not exist. Conjugation is given as example.
Affirmation
Simple form
I could arc arc you could arc arc he could arc arc we could arc arc you could arc arc they could arc arc
V-ing form
I could be arc arcing you could be arc arcing he could be arc arcing we could be arc arcing you could be arc arcing they could be arc arcing
Perfect
I could have arc arced you could have arc arced he could have arc arced we could have arc arced you could have arc arced they could have arc arced
V-ing perfect
I could have been arc arcing you could have been arc arcing he could have been arc arcing we could have been arc arcing you could have been arc arcing they could have been arc arcing
Negation
Simple form
I could not arc arc you could not arc arc he could not arc arc we could not arc arc you could not arc arc they could not arc arc
V-ing form
I could not be arc arcing you could not be arc arcing he could not be arc arcing we could not be arc arcing you could not be arc arcing they could not be arc arcing
Perfect
I could not have arc arced you could not have arc arced he could not have arc arced we could not have arc arced you could not have arc arced they could not have arc arced
V-ing perfect
I could not have been arc arcing you could not have been arc arcing he could not have been arc arcing we could not have been arc arcing you could not have been arc arcing they could not have been arc arcing
Interrogative form
Simple form
could I arc arc? could you arc arc? could he arc arc? could we arc arc? could you arc arc? could they arc arc?
V-ing form
could I be arc arcing? could you be arc arcing? could he be arc arcing? could we be arc arcing? could you be arc arcing? could they be arc arcing?
Perfect
could I have arc arced? could you have arc arced? could he have arc arced? could we have arc arced? could you have arc arced? could they have arc arced?
V-ing perfect
could I have been arc arcing? could you have been arc arcing? could he have been arc arcing? could we have been arc arcing? could you have been arc arcing? could they have been arc arcing?
Interro-negative form
Simple form
could I not arc arc? could you not arc arc? could he not arc arc? could we not arc arc? could you not arc arc? could they not arc arc?
V-ing form
could I not be arc arcing? could you not be arc arcing? could he not be arc arcing? could we not be arc arcing? could you not be arc arcing? could they not be arc arcing?
Perfect
could I not have arc arced? could you not have arc arced? could he not have arc arced? could we not have arc arced? could you not have arc arced? could they not have arc arced?
V-ing perfect
could I not have been arc arcing? could you not have been arc arcing? could he not have been arc arcing? could we not have been arc arcing? could you not have been arc arcing? could they not have been arc arcing?