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