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 could not cycle you could not cycle he could not cycle we could not cycle you could not cycle they could not cycle
V-ing form
I could not be cycling you could not be cycling he could not be cycling we could not be cycling you could not be cycling they could not be cycling
Perfect
I could not have cycled you could not have cycled he could not have cycled we could not have cycled you could not have cycled they could not have cycled
V-ing perfect
I could not have been cycling you could not have been cycling he could not have been cycling we could not have been cycling you could not have been cycling they could not 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
could I not cycle? could you not cycle? could he not cycle? could we not cycle? could you not cycle? could they not cycle?
V-ing form
could I not be cycling? could you not be cycling? could he not be cycling? could we not be cycling? could you not be cycling? could they not be cycling?
Perfect
could I not have cycled? could you not have cycled? could he not have cycled? could we not have cycled? could you not have cycled? could they not have cycled?
V-ing perfect
could I not have been cycling? could you not have been cycling? could he not have been cycling? could we not have been cycling? could you not have been cycling? could they not have been cycling?