I could suppress you could suppress he could suppress we could suppress you could suppress they could suppress
V-ing form
I could be suppressing you could be suppressing he could be suppressing we could be suppressing you could be suppressing they could be suppressing
Perfect
I could have suppressed you could have suppressed he could have suppressed we could have suppressed you could have suppressed they could have suppressed
V-ing perfect
I could have been suppressing you could have been suppressing he could have been suppressing we could have been suppressing you could have been suppressing they could have been suppressing
Negation
Simple form
I could not suppress you could not suppress he could not suppress we could not suppress you could not suppress they could not suppress
V-ing form
I could not be suppressing you could not be suppressing he could not be suppressing we could not be suppressing you could not be suppressing they could not be suppressing
Perfect
I could not have suppressed you could not have suppressed he could not have suppressed we could not have suppressed you could not have suppressed they could not have suppressed
V-ing perfect
I could not have been suppressing you could not have been suppressing he could not have been suppressing we could not have been suppressing you could not have been suppressing they could not have been suppressing
Interrogative form
Simple form
could I suppress? could you suppress? could he suppress? could we suppress? could you suppress? could they suppress?
V-ing form
could I be suppressing? could you be suppressing? could he be suppressing? could we be suppressing? could you be suppressing? could they be suppressing?
Perfect
could I have suppressed? could you have suppressed? could he have suppressed? could we have suppressed? could you have suppressed? could they have suppressed?
V-ing perfect
could I have been suppressing? could you have been suppressing? could he have been suppressing? could we have been suppressing? could you have been suppressing? could they have been suppressing?
Interro-negative form
Simple form
could I not suppress? could you not suppress? could he not suppress? could we not suppress? could you not suppress? could they not suppress?
V-ing form
could I not be suppressing? could you not be suppressing? could he not be suppressing? could we not be suppressing? could you not be suppressing? could they not be suppressing?
Perfect
could I not have suppressed? could you not have suppressed? could he not have suppressed? could we not have suppressed? could you not have suppressed? could they not have suppressed?
V-ing perfect
could I not have been suppressing? could you not have been suppressing? could he not have been suppressing? could we not have been suppressing? could you not have been suppressing? could they not have been suppressing?