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