English verb conjugation
COULD OK

Regular verb: ok - oked - oked

Affirmation

Simple form	V-ing form
I could ok you could ok he could ok we could ok you could ok they could ok	I could be oking you could be oking he could be oking we could be oking you could be oking they could be oking
Perfect	V-ing perfect
I could have oked you could have oked he could have oked we could have oked you could have oked they could have oked	I could have been oking you could have been oking he could have been oking we could have been oking you could have been oking they could have been oking

Negation

Simple form	V-ing form
I could not ok you could not ok he could not ok we could not ok you could not ok they could not ok	I could not be oking you could not be oking he could not be oking we could not be oking you could not be oking they could not be oking
Perfect	V-ing perfect
I could not have oked you could not have oked he could not have oked we could not have oked you could not have oked they could not have oked	I could not have been oking you could not have been oking he could not have been oking we could not have been oking you could not have been oking they could not have been oking

Interrogative form

Simple form	V-ing form
could I ok? could you ok? could he ok? could we ok? could you ok? could they ok?	could I be oking? could you be oking? could he be oking? could we be oking? could you be oking? could they be oking?
Perfect	V-ing perfect
could I have oked? could you have oked? could he have oked? could we have oked? could you have oked? could they have oked?	could I have been oking? could you have been oking? could he have been oking? could we have been oking? could you have been oking? could they have been oking?

Interro-negative form

Simple form	V-ing form
could I not ok? could you not ok? could he not ok? could we not ok? could you not ok? could they not ok?	could I not be oking? could you not be oking? could he not be oking? could we not be oking? could you not be oking? could they not be oking?
Perfect	V-ing perfect
could I not have oked? could you not have oked? could he not have oked? could we not have oked? could you not have oked? could they not have oked?	could I not have been oking? could you not have been oking? could he not have been oking? could we not have been oking? could you not have been oking? could they not have been oking?