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 couldn't null you couldn't null she couldn't null we couldn't null you couldn't null they couldn't null	I couldn't be nulling you couldn't be nulling she couldn't be nulling we couldn't be nulling you couldn't be nulling they couldn't be nulling
Perfect	V-ing perfect
I couldn't have nulled you couldn't have nulled she couldn't have nulled we couldn't have nulled you couldn't have nulled they couldn't have nulled	I couldn't have been nulling you couldn't have been nulling she couldn't have been nulling we couldn't have been nulling you couldn't have been nulling they couldn't 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
couldn't I null? couldn't you null? couldn't she null? couldn't we null? couldn't you null? couldn't they null?	couldn't I be nulling? couldn't you be nulling? couldn't she be nulling? couldn't we be nulling? couldn't you be nulling? couldn't they be nulling?
Perfect	V-ing perfect
couldn't I have nulled? couldn't you have nulled? couldn't she have nulled? couldn't we have nulled? couldn't you have nulled? couldn't they have nulled?	couldn't I have been nulling? couldn't you have been nulling? couldn't she have been nulling? couldn't we have been nulling? couldn't you have been nulling? couldn't they have been nulling?