English verb conjugation
COULD TUN

Regular verb: tun - tuned - tuned

Affirmation

Simple form	V-ing form
I could tun you could tun she could tun we could tun you could tun they could tun	I could be tuning you could be tuning she could be tuning we could be tuning you could be tuning they could be tuning
Perfect	V-ing perfect
I could have tuned you could have tuned she could have tuned we could have tuned you could have tuned they could have tuned	I could have been tuning you could have been tuning she could have been tuning we could have been tuning you could have been tuning they could have been tuning

Negation

Simple form	V-ing form
I could not tun you could not tun she could not tun we could not tun you could not tun they could not tun	I could not be tuning you could not be tuning she could not be tuning we could not be tuning you could not be tuning they could not be tuning
Perfect	V-ing perfect
I could not have tuned you could not have tuned she could not have tuned we could not have tuned you could not have tuned they could not have tuned	I could not have been tuning you could not have been tuning she could not have been tuning we could not have been tuning you could not have been tuning they could not have been tuning

Interrogative form

Simple form	V-ing form
could I tun? could you tun? could she tun? could we tun? could you tun? could they tun?	could I be tuning? could you be tuning? could she be tuning? could we be tuning? could you be tuning? could they be tuning?
Perfect	V-ing perfect
could I have tuned? could you have tuned? could she have tuned? could we have tuned? could you have tuned? could they have tuned?	could I have been tuning? could you have been tuning? could she have been tuning? could we have been tuning? could you have been tuning? could they have been tuning?

Interro-negative form

Simple form	V-ing form
could I not tun? could you not tun? could she not tun? could we not tun? could you not tun? could they not tun?	could I not be tuning? could you not be tuning? could she not be tuning? could we not be tuning? could you not be tuning? could they not be tuning?
Perfect	V-ing perfect
could I not have tuned? could you not have tuned? could she not have tuned? could we not have tuned? could you not have tuned? could they not have tuned?	could I not have been tuning? could you not have been tuning? could she not have been tuning? could we not have been tuning? could you not have been tuning? could they not have been tuning?