English verb conjugation
COULD RETROGRESS

Regular verb: retrogress - retrogressed - retrogressed

Affirmation

Simple form	V-ing form
I could retrogress you could retrogress she could retrogress we could retrogress you could retrogress they could retrogress	I could be retrogressing you could be retrogressing she could be retrogressing we could be retrogressing you could be retrogressing they could be retrogressing
Perfect	V-ing perfect
I could have retrogressed you could have retrogressed she could have retrogressed we could have retrogressed you could have retrogressed they could have retrogressed	I could have been retrogressing you could have been retrogressing she could have been retrogressing we could have been retrogressing you could have been retrogressing they could have been retrogressing

Negation

Simple form	V-ing form
I could not retrogress you could not retrogress she could not retrogress we could not retrogress you could not retrogress they could not retrogress	I could not be retrogressing you could not be retrogressing she could not be retrogressing we could not be retrogressing you could not be retrogressing they could not be retrogressing
Perfect	V-ing perfect
I could not have retrogressed you could not have retrogressed she could not have retrogressed we could not have retrogressed you could not have retrogressed they could not have retrogressed	I could not have been retrogressing you could not have been retrogressing she could not have been retrogressing we could not have been retrogressing you could not have been retrogressing they could not have been retrogressing

Interrogative form

Simple form	V-ing form
could I retrogress? could you retrogress? could she retrogress? could we retrogress? could you retrogress? could they retrogress?	could I be retrogressing? could you be retrogressing? could she be retrogressing? could we be retrogressing? could you be retrogressing? could they be retrogressing?
Perfect	V-ing perfect
could I have retrogressed? could you have retrogressed? could she have retrogressed? could we have retrogressed? could you have retrogressed? could they have retrogressed?	could I have been retrogressing? could you have been retrogressing? could she have been retrogressing? could we have been retrogressing? could you have been retrogressing? could they have been retrogressing?

Interro-negative form

Simple form	V-ing form
could I not retrogress? could you not retrogress? could she not retrogress? could we not retrogress? could you not retrogress? could they not retrogress?	could I not be retrogressing? could you not be retrogressing? could she not be retrogressing? could we not be retrogressing? could you not be retrogressing? could they not be retrogressing?
Perfect	V-ing perfect
could I not have retrogressed? could you not have retrogressed? could she not have retrogressed? could we not have retrogressed? could you not have retrogressed? could they not have retrogressed?	could I not have been retrogressing? could you not have been retrogressing? could she not have been retrogressing? could we not have been retrogressing? could you not have been retrogressing? could they not have been retrogressing?