I could progress you could progress he could progress we could progress you could progress they could progress
V-ing form
I could be progressing you could be progressing he could be progressing we could be progressing you could be progressing they could be progressing
Perfect
I could have progressed you could have progressed he could have progressed we could have progressed you could have progressed they could have progressed
V-ing perfect
I could have been progressing you could have been progressing he could have been progressing we could have been progressing you could have been progressing they could have been progressing
Negation
Simple form
I could not progress you could not progress he could not progress we could not progress you could not progress they could not progress
V-ing form
I could not be progressing you could not be progressing he could not be progressing we could not be progressing you could not be progressing they could not be progressing
Perfect
I could not have progressed you could not have progressed he could not have progressed we could not have progressed you could not have progressed they could not have progressed
V-ing perfect
I could not have been progressing you could not have been progressing he could not have been progressing we could not have been progressing you could not have been progressing they could not have been progressing
Interrogative form
Simple form
could I progress? could you progress? could he progress? could we progress? could you progress? could they progress?
V-ing form
could I be progressing? could you be progressing? could he be progressing? could we be progressing? could you be progressing? could they be progressing?
Perfect
could I have progressed? could you have progressed? could he have progressed? could we have progressed? could you have progressed? could they have progressed?
V-ing perfect
could I have been progressing? could you have been progressing? could he have been progressing? could we have been progressing? could you have been progressing? could they have been progressing?
Interro-negative form
Simple form
could I not progress? could you not progress? could he not progress? could we not progress? could you not progress? could they not progress?
V-ing form
could I not be progressing? could you not be progressing? could he not be progressing? could we not be progressing? could you not be progressing? could they not be progressing?
Perfect
could I not have progressed? could you not have progressed? could he not have progressed? could we not have progressed? could you not have progressed? could they not have progressed?
V-ing perfect
could I not have been progressing? could you not have been progressing? could he not have been progressing? could we not have been progressing? could you not have been progressing? could they not have been progressing?