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 couldn't yarn you couldn't yarn she couldn't yarn we couldn't yarn you couldn't yarn they couldn't yarn	I couldn't be yarning you couldn't be yarning she couldn't be yarning we couldn't be yarning you couldn't be yarning they couldn't be yarning
Perfect	V-ing perfect
I couldn't have yarned you couldn't have yarned she couldn't have yarned we couldn't have yarned you couldn't have yarned they couldn't have yarned	I couldn't have been yarning you couldn't have been yarning she couldn't have been yarning we couldn't have been yarning you couldn't have been yarning they couldn't 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
couldn't I yarn? couldn't you yarn? couldn't she yarn? couldn't we yarn? couldn't you yarn? couldn't they yarn?	couldn't I be yarning? couldn't you be yarning? couldn't she be yarning? couldn't we be yarning? couldn't you be yarning? couldn't they be yarning?
Perfect	V-ing perfect
couldn't I have yarned? couldn't you have yarned? couldn't she have yarned? couldn't we have yarned? couldn't you have yarned? couldn't they have yarned?	couldn't I have been yarning? couldn't you have been yarning? couldn't she have been yarning? couldn't we have been yarning? couldn't you have been yarning? couldn't they have been yarning?