English verb conjugation
COULD BS

Regular verb: bs - bsed - bsed

Affirmation

Simple form	V-ing form
I could bs you could bs he could bs we could bs you could bs they could bs	I could be bsing you could be bsing he could be bsing we could be bsing you could be bsing they could be bsing
Perfect	V-ing perfect
I could have bsed you could have bsed he could have bsed we could have bsed you could have bsed they could have bsed	I could have been bsing you could have been bsing he could have been bsing we could have been bsing you could have been bsing they could have been bsing

Negation

Simple form	V-ing form
I couldn't bs you couldn't bs he couldn't bs we couldn't bs you couldn't bs they couldn't bs	I couldn't be bsing you couldn't be bsing he couldn't be bsing we couldn't be bsing you couldn't be bsing they couldn't be bsing
Perfect	V-ing perfect
I couldn't have bsed you couldn't have bsed he couldn't have bsed we couldn't have bsed you couldn't have bsed they couldn't have bsed	I couldn't have been bsing you couldn't have been bsing he couldn't have been bsing we couldn't have been bsing you couldn't have been bsing they couldn't have been bsing

Interrogative form

Simple form	V-ing form
could I bs? could you bs? could he bs? could we bs? could you bs? could they bs?	could I be bsing? could you be bsing? could he be bsing? could we be bsing? could you be bsing? could they be bsing?
Perfect	V-ing perfect
could I have bsed? could you have bsed? could he have bsed? could we have bsed? could you have bsed? could they have bsed?	could I have been bsing? could you have been bsing? could he have been bsing? could we have been bsing? could you have been bsing? could they have been bsing?

Interro-negative form

Simple form	V-ing form
couldn't I bs? couldn't you bs? couldn't he bs? couldn't we bs? couldn't you bs? couldn't they bs?	couldn't I be bsing? couldn't you be bsing? couldn't he be bsing? couldn't we be bsing? couldn't you be bsing? couldn't they be bsing?
Perfect	V-ing perfect
couldn't I have bsed? couldn't you have bsed? couldn't he have bsed? couldn't we have bsed? couldn't you have bsed? couldn't they have bsed?	couldn't I have been bsing? couldn't you have been bsing? couldn't he have been bsing? couldn't we have been bsing? couldn't you have been bsing? couldn't they have been bsing?