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