I could blinker you could blinker she could blinker we could blinker you could blinker they could blinker
V-ing form
I could be blinkering you could be blinkering she could be blinkering we could be blinkering you could be blinkering they could be blinkering
Perfect
I could have blinkered you could have blinkered she could have blinkered we could have blinkered you could have blinkered they could have blinkered
V-ing perfect
I could have been blinkering you could have been blinkering she could have been blinkering we could have been blinkering you could have been blinkering they could have been blinkering
Negation
Simple form
I couldn't blinker you couldn't blinker she couldn't blinker we couldn't blinker you couldn't blinker they couldn't blinker
V-ing form
I couldn't be blinkering you couldn't be blinkering she couldn't be blinkering we couldn't be blinkering you couldn't be blinkering they couldn't be blinkering
Perfect
I couldn't have blinkered you couldn't have blinkered she couldn't have blinkered we couldn't have blinkered you couldn't have blinkered they couldn't have blinkered
V-ing perfect
I couldn't have been blinkering you couldn't have been blinkering she couldn't have been blinkering we couldn't have been blinkering you couldn't have been blinkering they couldn't have been blinkering
Interrogative form
Simple form
could I blinker? could you blinker? could she blinker? could we blinker? could you blinker? could they blinker?
V-ing form
could I be blinkering? could you be blinkering? could she be blinkering? could we be blinkering? could you be blinkering? could they be blinkering?
Perfect
could I have blinkered? could you have blinkered? could she have blinkered? could we have blinkered? could you have blinkered? could they have blinkered?
V-ing perfect
could I have been blinkering? could you have been blinkering? could she have been blinkering? could we have been blinkering? could you have been blinkering? could they have been blinkering?
Interro-negative form
Simple form
couldn't I blinker? couldn't you blinker? couldn't she blinker? couldn't we blinker? couldn't you blinker? couldn't they blinker?
V-ing form
couldn't I be blinkering? couldn't you be blinkering? couldn't she be blinkering? couldn't we be blinkering? couldn't you be blinkering? couldn't they be blinkering?
Perfect
couldn't I have blinkered? couldn't you have blinkered? couldn't she have blinkered? couldn't we have blinkered? couldn't you have blinkered? couldn't they have blinkered?
V-ing perfect
couldn't I have been blinkering? couldn't you have been blinkering? couldn't she have been blinkering? couldn't we have been blinkering? couldn't you have been blinkering? couldn't they have been blinkering?