English verb conjugation
COULD YARN

Regular verb: yarn - yarned - yarned

Affirmation

Simple form	V-ing form
I could yarn you could yarn she could yarn we could yarn you could yarn they could yarn	I could be yarning you could be yarning she could be yarning we could be yarning you could be yarning they could be yarning
Perfect	V-ing perfect
I could have yarned you could have yarned she could have yarned we could have yarned you could have yarned they could have yarned	I could have been yarning you could have been yarning she could have been yarning we could have been yarning you could have been yarning they could have been yarning

Negation

Simple form	V-ing form
I could not yarn you could not yarn she could not yarn we could not yarn you could not yarn they could not yarn	I could not be yarning you could not be yarning she could not be yarning we could not be yarning you could not be yarning they could not be yarning
Perfect	V-ing perfect
I could not have yarned you could not have yarned she could not have yarned we could not have yarned you could not have yarned they could not have yarned	I could not have been yarning you could not have been yarning she could not have been yarning we could not have been yarning you could not have been yarning they could not have been yarning

Interrogative form

Simple form	V-ing form
could I yarn? could you yarn? could she yarn? could we yarn? could you yarn? could they yarn?	could I be yarning? could you be yarning? could she be yarning? could we be yarning? could you be yarning? could they be yarning?
Perfect	V-ing perfect
could I have yarned? could you have yarned? could she have yarned? could we have yarned? could you have yarned? could they have yarned?	could I have been yarning? could you have been yarning? could she have been yarning? could we have been yarning? could you have been yarning? could they have been yarning?

Interro-negative form

Simple form	V-ing form
could I not yarn? could you not yarn? could she not yarn? could we not yarn? could you not yarn? could they not yarn?	could I not be yarning? could you not be yarning? could she not be yarning? could we not be yarning? could you not be yarning? could they not be yarning?
Perfect	V-ing perfect
could I not have yarned? could you not have yarned? could she not have yarned? could we not have yarned? could you not have yarned? could they not have yarned?	could I not have been yarning? could you not have been yarning? could she not have been yarning? could we not have been yarning? could you not have been yarning? could they not have been yarning?