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