I could display you could display he could display we could display you could display they could display
V-ing form
I could be displaying you could be displaying he could be displaying we could be displaying you could be displaying they could be displaying
Perfect
I could have displayed you could have displayed he could have displayed we could have displayed you could have displayed they could have displayed
V-ing perfect
I could have been displaying you could have been displaying he could have been displaying we could have been displaying you could have been displaying they could have been displaying
Negation
Simple form
I could not display you could not display he could not display we could not display you could not display they could not display
V-ing form
I could not be displaying you could not be displaying he could not be displaying we could not be displaying you could not be displaying they could not be displaying
Perfect
I could not have displayed you could not have displayed he could not have displayed we could not have displayed you could not have displayed they could not have displayed
V-ing perfect
I could not have been displaying you could not have been displaying he could not have been displaying we could not have been displaying you could not have been displaying they could not have been displaying
Interrogative form
Simple form
could I display? could you display? could he display? could we display? could you display? could they display?
V-ing form
could I be displaying? could you be displaying? could he be displaying? could we be displaying? could you be displaying? could they be displaying?
Perfect
could I have displayed? could you have displayed? could he have displayed? could we have displayed? could you have displayed? could they have displayed?
V-ing perfect
could I have been displaying? could you have been displaying? could he have been displaying? could we have been displaying? could you have been displaying? could they have been displaying?
Interro-negative form
Simple form
could I not display? could you not display? could he not display? could we not display? could you not display? could they not display?
V-ing form
could I not be displaying? could you not be displaying? could he not be displaying? could we not be displaying? could you not be displaying? could they not be displaying?
Perfect
could I not have displayed? could you not have displayed? could he not have displayed? could we not have displayed? could you not have displayed? could they not have displayed?
V-ing perfect
could I not have been displaying? could you not have been displaying? could he not have been displaying? could we not have been displaying? could you not have been displaying? could they not have been displaying?