I could criticize you could criticize he could criticize we could criticize you could criticize they could criticize
V-ing form
I could be criticizing you could be criticizing he could be criticizing we could be criticizing you could be criticizing they could be criticizing
Perfect
I could have criticized you could have criticized he could have criticized we could have criticized you could have criticized they could have criticized
V-ing perfect
I could have been criticizing you could have been criticizing he could have been criticizing we could have been criticizing you could have been criticizing they could have been criticizing
Negation
Simple form
I couldn't criticize you couldn't criticize he couldn't criticize we couldn't criticize you couldn't criticize they couldn't criticize
V-ing form
I couldn't be criticizing you couldn't be criticizing he couldn't be criticizing we couldn't be criticizing you couldn't be criticizing they couldn't be criticizing
Perfect
I couldn't have criticized you couldn't have criticized he couldn't have criticized we couldn't have criticized you couldn't have criticized they couldn't have criticized
V-ing perfect
I couldn't have been criticizing you couldn't have been criticizing he couldn't have been criticizing we couldn't have been criticizing you couldn't have been criticizing they couldn't have been criticizing
Interrogative form
Simple form
could I criticize? could you criticize? could he criticize? could we criticize? could you criticize? could they criticize?
V-ing form
could I be criticizing? could you be criticizing? could he be criticizing? could we be criticizing? could you be criticizing? could they be criticizing?
Perfect
could I have criticized? could you have criticized? could he have criticized? could we have criticized? could you have criticized? could they have criticized?
V-ing perfect
could I have been criticizing? could you have been criticizing? could he have been criticizing? could we have been criticizing? could you have been criticizing? could they have been criticizing?
Interro-negative form
Simple form
couldn't I criticize? couldn't you criticize? couldn't he criticize? couldn't we criticize? couldn't you criticize? couldn't they criticize?
V-ing form
couldn't I be criticizing? couldn't you be criticizing? couldn't he be criticizing? couldn't we be criticizing? couldn't you be criticizing? couldn't they be criticizing?
Perfect
couldn't I have criticized? couldn't you have criticized? couldn't he have criticized? couldn't we have criticized? couldn't you have criticized? couldn't they have criticized?
V-ing perfect
couldn't I have been criticizing? couldn't you have been criticizing? couldn't he have been criticizing? couldn't we have been criticizing? couldn't you have been criticizing? couldn't they have been criticizing?