I could prestress you could prestress he could prestress we could prestress you could prestress they could prestress
V-ing form
I could be prestressing you could be prestressing he could be prestressing we could be prestressing you could be prestressing they could be prestressing
Perfect
I could have prestressed you could have prestressed he could have prestressed we could have prestressed you could have prestressed they could have prestressed
V-ing perfect
I could have been prestressing you could have been prestressing he could have been prestressing we could have been prestressing you could have been prestressing they could have been prestressing
Negation
Simple form
I could not prestress you could not prestress he could not prestress we could not prestress you could not prestress they could not prestress
V-ing form
I could not be prestressing you could not be prestressing he could not be prestressing we could not be prestressing you could not be prestressing they could not be prestressing
Perfect
I could not have prestressed you could not have prestressed he could not have prestressed we could not have prestressed you could not have prestressed they could not have prestressed
V-ing perfect
I could not have been prestressing you could not have been prestressing he could not have been prestressing we could not have been prestressing you could not have been prestressing they could not have been prestressing
Interrogative form
Simple form
could I prestress? could you prestress? could he prestress? could we prestress? could you prestress? could they prestress?
V-ing form
could I be prestressing? could you be prestressing? could he be prestressing? could we be prestressing? could you be prestressing? could they be prestressing?
Perfect
could I have prestressed? could you have prestressed? could he have prestressed? could we have prestressed? could you have prestressed? could they have prestressed?
V-ing perfect
could I have been prestressing? could you have been prestressing? could he have been prestressing? could we have been prestressing? could you have been prestressing? could they have been prestressing?
Interro-negative form
Simple form
could I not prestress? could you not prestress? could he not prestress? could we not prestress? could you not prestress? could they not prestress?
V-ing form
could I not be prestressing? could you not be prestressing? could he not be prestressing? could we not be prestressing? could you not be prestressing? could they not be prestressing?
Perfect
could I not have prestressed? could you not have prestressed? could he not have prestressed? could we not have prestressed? could you not have prestressed? could they not have prestressed?
V-ing perfect
could I not have been prestressing? could you not have been prestressing? could he not have been prestressing? could we not have been prestressing? could you not have been prestressing? could they not have been prestressing?