I could sponsor you could sponsor he could sponsor we could sponsor you could sponsor they could sponsor
V-ing form
I could be sponsoring you could be sponsoring he could be sponsoring we could be sponsoring you could be sponsoring they could be sponsoring
Perfect
I could have sponsored you could have sponsored he could have sponsored we could have sponsored you could have sponsored they could have sponsored
V-ing perfect
I could have been sponsoring you could have been sponsoring he could have been sponsoring we could have been sponsoring you could have been sponsoring they could have been sponsoring
Negation
Simple form
I could not sponsor you could not sponsor he could not sponsor we could not sponsor you could not sponsor they could not sponsor
V-ing form
I could not be sponsoring you could not be sponsoring he could not be sponsoring we could not be sponsoring you could not be sponsoring they could not be sponsoring
Perfect
I could not have sponsored you could not have sponsored he could not have sponsored we could not have sponsored you could not have sponsored they could not have sponsored
V-ing perfect
I could not have been sponsoring you could not have been sponsoring he could not have been sponsoring we could not have been sponsoring you could not have been sponsoring they could not have been sponsoring
Interrogative form
Simple form
could I sponsor? could you sponsor? could he sponsor? could we sponsor? could you sponsor? could they sponsor?
V-ing form
could I be sponsoring? could you be sponsoring? could he be sponsoring? could we be sponsoring? could you be sponsoring? could they be sponsoring?
Perfect
could I have sponsored? could you have sponsored? could he have sponsored? could we have sponsored? could you have sponsored? could they have sponsored?
V-ing perfect
could I have been sponsoring? could you have been sponsoring? could he have been sponsoring? could we have been sponsoring? could you have been sponsoring? could they have been sponsoring?
Interro-negative form
Simple form
could I not sponsor? could you not sponsor? could he not sponsor? could we not sponsor? could you not sponsor? could they not sponsor?
V-ing form
could I not be sponsoring? could you not be sponsoring? could he not be sponsoring? could we not be sponsoring? could you not be sponsoring? could they not be sponsoring?
Perfect
could I not have sponsored? could you not have sponsored? could he not have sponsored? could we not have sponsored? could you not have sponsored? could they not have sponsored?
V-ing perfect
could I not have been sponsoring? could you not have been sponsoring? could he not have been sponsoring? could we not have been sponsoring? could you not have been sponsoring? could they not have been sponsoring?