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