could roister
Verbe régulier : roister - roistered- roistered

Affirmation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I could roister
you could roister
he could roister
we could roister
you could roister
they could roister 	I could be roistering
you could be roistering
he could be roistering
we could be roistering
you could be roistering
they could be roistering	I could have roistered
you could have roistered
he could have roistered
we could have roistered
you could have roistered
they could have roistered	I could have been roistering
you could have been roistering
he could have been roistering
we could have been roistering
you could have been roistering
they could have been roistering	

Négation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I could not roister
you could not roister
he could not roister
we could not roister
you could not roister
they could not roister 	I could not be roistering
you could not be roistering
he could not be roistering
we could not be roistering
you could not be roistering
they could not be roistering	I could not have roistered
you could not have roistered
he could not have roistered
we could not have roistered
you could not have roistered
they could not have roistered	I could not have been roistering
you could not have been roistering
he could not have been roistering
we could not have been roistering
you could not have been roistering
they could not have been roistering	

Forme interrogative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
could I roister?
could you roister?
could he roister?
could we roister?
could you roister?
could they roister? 	could I be roistering?
could you be roistering?
could he be roistering?
could we be roistering?
could you be roistering?
could they be roistering? 	could I have roistered?
could you have roistered?
could he have roistered?
could we have roistered?
could you have roistered?
could they have roistered? 	could I have been roistering?
could you have been roistering?
could he have been roistering?
could we have been roistering?
could you have been roistering?
could they have been roistering? 	

Forme interro-négative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
could I not roister?
could you not roister?
could he not roister?
could we not roister?
could you not roister?
could they not roister? 	could I not be roistering?
could you not be roistering?
could he not be roistering?
could we not be roistering?
could you not be roistering?
could they not be roistering? 	could I not have roistered?
could you not have roistered?
could he not have roistered?
could we not have roistered?
could you not have roistered?
could they not have roistered? 	could I not have been roistering?
could you not have been roistering?
could he not have been roistering?
could we not have been roistering?
could you not have been roistering?
could they not have been roistering?