English verb conjugation
COULD UNTACK

Regular verb: untack - untacked - untacked

Affirmation

Simple form	V-ing form
I could untack you could untack he could untack we could untack you could untack they could untack	I could be untacking you could be untacking he could be untacking we could be untacking you could be untacking they could be untacking
Perfect	V-ing perfect
I could have untacked you could have untacked he could have untacked we could have untacked you could have untacked they could have untacked	I could have been untacking you could have been untacking he could have been untacking we could have been untacking you could have been untacking they could have been untacking

Negation

Simple form	V-ing form
I could not untack you could not untack he could not untack we could not untack you could not untack they could not untack	I could not be untacking you could not be untacking he could not be untacking we could not be untacking you could not be untacking they could not be untacking
Perfect	V-ing perfect
I could not have untacked you could not have untacked he could not have untacked we could not have untacked you could not have untacked they could not have untacked	I could not have been untacking you could not have been untacking he could not have been untacking we could not have been untacking you could not have been untacking they could not have been untacking

Interrogative form

Simple form	V-ing form
could I untack? could you untack? could he untack? could we untack? could you untack? could they untack?	could I be untacking? could you be untacking? could he be untacking? could we be untacking? could you be untacking? could they be untacking?
Perfect	V-ing perfect
could I have untacked? could you have untacked? could he have untacked? could we have untacked? could you have untacked? could they have untacked?	could I have been untacking? could you have been untacking? could he have been untacking? could we have been untacking? could you have been untacking? could they have been untacking?

Interro-negative form

Simple form	V-ing form
could I not untack? could you not untack? could he not untack? could we not untack? could you not untack? could they not untack?	could I not be untacking? could you not be untacking? could he not be untacking? could we not be untacking? could you not be untacking? could they not be untacking?
Perfect	V-ing perfect
could I not have untacked? could you not have untacked? could he not have untacked? could we not have untacked? could you not have untacked? could they not have untacked?	could I not have been untacking? could you not have been untacking? could he not have been untacking? could we not have been untacking? could you not have been untacking? could they not have been untacking?