could rib
Regular verb: rib - ribed- ribed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could rib
you could rib
she could rib
we could rib
you could rib
they could rib 	I could be ribing
you could be ribing
she could be ribing
we could be ribing
you could be ribing
they could be ribing	I could have ribed
you could have ribed
she could have ribed
we could have ribed
you could have ribed
they could have ribed	I could have been ribing
you could have been ribing
she could have been ribing
we could have been ribing
you could have been ribing
they could have been ribing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't rib
you couldn't rib
she couldn't rib
we couldn't rib
you couldn't rib
they couldn't rib 	I couldn't be ribing
you couldn't be ribing
she couldn't be ribing
we couldn't be ribing
you couldn't be ribing
they couldn't be ribing	I couldn't have ribed
you couldn't have ribed
she couldn't have ribed
we couldn't have ribed
you couldn't have ribed
they couldn't have ribed	I couldn't have been ribing
you couldn't have been ribing
she couldn't have been ribing
we couldn't have been ribing
you couldn't have been ribing
they couldn't have been ribing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I rib?
could you rib?
could she rib?
could we rib?
could you rib?
could they rib? 	could I be ribing?
could you be ribing?
could she be ribing?
could we be ribing?
could you be ribing?
could they be ribing? 	could I have ribed?
could you have ribed?
could she have ribed?
could we have ribed?
could you have ribed?
could they have ribed? 	could I have been ribing?
could you have been ribing?
could she have been ribing?
could we have been ribing?
could you have been ribing?
could they have been ribing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I rib?
couldn't you rib?
couldn't she rib?
couldn't we rib?
couldn't you rib?
couldn't they rib? 	couldn't I be ribing?
couldn't you be ribing?
couldn't she be ribing?
couldn't we be ribing?
couldn't you be ribing?
couldn't they be ribing? 	couldn't I have ribed?
couldn't you have ribed?
couldn't she have ribed?
couldn't we have ribed?
couldn't you have ribed?
couldn't they have ribed? 	couldn't I have been ribing?
couldn't you have been ribing?
couldn't she have been ribing?
couldn't we have been ribing?
couldn't you have been ribing?
couldn't they have been ribing?