English verb conjugation
COULD NULL

Regular verb: null - nulled - nulled

Affirmation

Simple form	V-ing form
I could null you could null she could null we could null you could null they could null	I could be nulling you could be nulling she could be nulling we could be nulling you could be nulling they could be nulling
Perfect	V-ing perfect
I could have nulled you could have nulled she could have nulled we could have nulled you could have nulled they could have nulled	I could have been nulling you could have been nulling she could have been nulling we could have been nulling you could have been nulling they could have been nulling

Negation

Simple form	V-ing form
I could not null you could not null she could not null we could not null you could not null they could not null	I could not be nulling you could not be nulling she could not be nulling we could not be nulling you could not be nulling they could not be nulling
Perfect	V-ing perfect
I could not have nulled you could not have nulled she could not have nulled we could not have nulled you could not have nulled they could not have nulled	I could not have been nulling you could not have been nulling she could not have been nulling we could not have been nulling you could not have been nulling they could not have been nulling

Interrogative form

Simple form	V-ing form
could I null? could you null? could she null? could we null? could you null? could they null?	could I be nulling? could you be nulling? could she be nulling? could we be nulling? could you be nulling? could they be nulling?
Perfect	V-ing perfect
could I have nulled? could you have nulled? could she have nulled? could we have nulled? could you have nulled? could they have nulled?	could I have been nulling? could you have been nulling? could she have been nulling? could we have been nulling? could you have been nulling? could they have been nulling?

Interro-negative form

Simple form	V-ing form
could I not null? could you not null? could she not null? could we not null? could you not null? could they not null?	could I not be nulling? could you not be nulling? could she not be nulling? could we not be nulling? could you not be nulling? could they not be nulling?
Perfect	V-ing perfect
could I not have nulled? could you not have nulled? could she not have nulled? could we not have nulled? could you not have nulled? could they not have nulled?	could I not have been nulling? could you not have been nulling? could she not have been nulling? could we not have been nulling? could you not have been nulling? could they not have been nulling?