I can bs you can bs he can bs we can bs you can bs they can bs
V-ing form
I can be bsing you can be bsing he can be bsing we can be bsing you can be bsing they can be bsing
Perfect
I can have bsed you can have bsed he can have bsed we can have bsed you can have bsed they can have bsed
V-ing perfect
I can have been bsing you can have been bsing he can have been bsing we can have been bsing you can have been bsing they can have been bsing
Negation
Simple form
I can't bs you can't bs he can't bs we can't bs you can't bs they can't bs
V-ing form
I can't be bsing you can't be bsing he can't be bsing we can't be bsing you can't be bsing they can't be bsing
Perfect
I can't have bsed you can't have bsed he can't have bsed we can't have bsed you can't have bsed they can't have bsed
V-ing perfect
I can't have been bsing you can't have been bsing he can't have been bsing we can't have been bsing you can't have been bsing they can't have been bsing
Interrogative form
Simple form
can I bs? can you bs? can he bs? can we bs? can you bs? can they bs?
V-ing form
can I be bsing? can you be bsing? can he be bsing? can we be bsing? can you be bsing? can they be bsing?
Perfect
can I have bsed? can you have bsed? can he have bsed? can we have bsed? can you have bsed? can they have bsed?
V-ing perfect
can I have been bsing? can you have been bsing? can he have been bsing? can we have been bsing? can you have been bsing? can they have been bsing?
Interro-negative form
Simple form
can't I bs? can't you bs? can't he bs? can't we bs? can't you bs? can't they bs?
V-ing form
can't I be bsing? can't you be bsing? can't he be bsing? can't we be bsing? can't you be bsing? can't they be bsing?
Perfect
can't I have bsed? can't you have bsed? can't he have bsed? can't we have bsed? can't you have bsed? can't they have bsed?
V-ing perfect
can't I have been bsing? can't you have been bsing? can't he have been bsing? can't we have been bsing? can't you have been bsing? can't they have been bsing?