I could bus you could bus she could bus we could bus you could bus they could bus
V-ing form
I could be bussing you could be bussing she could be bussing we could be bussing you could be bussing they could be bussing
Perfect
I could have bussed you could have bussed she could have bussed we could have bussed you could have bussed they could have bussed
V-ing perfect
I could have been bussing you could have been bussing she could have been bussing we could have been bussing you could have been bussing they could have been bussing
Negation
Simple form
I could not bus you could not bus she could not bus we could not bus you could not bus they could not bus
V-ing form
I could not be bussing you could not be bussing she could not be bussing we could not be bussing you could not be bussing they could not be bussing
Perfect
I could not have bussed you could not have bussed she could not have bussed we could not have bussed you could not have bussed they could not have bussed
V-ing perfect
I could not have been bussing you could not have been bussing she could not have been bussing we could not have been bussing you could not have been bussing they could not have been bussing
Interrogative form
Simple form
could I bus? could you bus? could she bus? could we bus? could you bus? could they bus?
V-ing form
could I be bussing? could you be bussing? could she be bussing? could we be bussing? could you be bussing? could they be bussing?
Perfect
could I have bussed? could you have bussed? could she have bussed? could we have bussed? could you have bussed? could they have bussed?
V-ing perfect
could I have been bussing? could you have been bussing? could she have been bussing? could we have been bussing? could you have been bussing? could they have been bussing?
Interro-negative form
Simple form
could I not bus? could you not bus? could she not bus? could we not bus? could you not bus? could they not bus?
V-ing form
could I not be bussing? could you not be bussing? could she not be bussing? could we not be bussing? could you not be bussing? could they not be bussing?
Perfect
could I not have bussed? could you not have bussed? could she not have bussed? could we not have bussed? could you not have bussed? could they not have bussed?
V-ing perfect
could I not have been bussing? could you not have been bussing? could she not have been bussing? could we not have been bussing? could you not have been bussing? could they not have been bussing?