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 couldn't progress you couldn't progress he couldn't progress we couldn't progress you couldn't progress they couldn't progress
V-ing form
I couldn't be progressing you couldn't be progressing he couldn't be progressing we couldn't be progressing you couldn't be progressing they couldn't be progressing
Perfect
I couldn't have progressed you couldn't have progressed he couldn't have progressed we couldn't have progressed you couldn't have progressed they couldn't have progressed
V-ing perfect
I couldn't have been progressing you couldn't have been progressing he couldn't have been progressing we couldn't have been progressing you couldn't have been progressing they couldn't 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
couldn't I progress? couldn't you progress? couldn't he progress? couldn't we progress? couldn't you progress? couldn't they progress?
V-ing form
couldn't I be progressing? couldn't you be progressing? couldn't he be progressing? couldn't we be progressing? couldn't you be progressing? couldn't they be progressing?
Perfect
couldn't I have progressed? couldn't you have progressed? couldn't he have progressed? couldn't we have progressed? couldn't you have progressed? couldn't they have progressed?
V-ing perfect
couldn't I have been progressing? couldn't you have been progressing? couldn't he have been progressing? couldn't we have been progressing? couldn't you have been progressing? couldn't they have been progressing?