could abstain
Verbo regular: abstain - abstained- abstained

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could abstain
you could abstain
she could abstain
we could abstain
you could abstain
they could abstain 	I could be abstaining
you could be abstaining
she could be abstaining
we could be abstaining
you could be abstaining
they could be abstaining	I could have abstained
you could have abstained
she could have abstained
we could have abstained
you could have abstained
they could have abstained	I could have been abstaining
you could have been abstaining
she could have been abstaining
we could have been abstaining
you could have been abstaining
they could have been abstaining	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could not abstain
you could not abstain
she could not abstain
we could not abstain
you could not abstain
they could not abstain 	I could not be abstaining
you could not be abstaining
she could not be abstaining
we could not be abstaining
you could not be abstaining
they could not be abstaining	I could not have abstained
you could not have abstained
she could not have abstained
we could not have abstained
you could not have abstained
they could not have abstained	I could not have been abstaining
you could not have been abstaining
she could not have been abstaining
we could not have been abstaining
you could not have been abstaining
they could not have been abstaining	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I abstain?
could you abstain?
could she abstain?
could we abstain?
could you abstain?
could they abstain? 	could I be abstaining?
could you be abstaining?
could she be abstaining?
could we be abstaining?
could you be abstaining?
could they be abstaining? 	could I have abstained?
could you have abstained?
could she have abstained?
could we have abstained?
could you have abstained?
could they have abstained? 	could I have been abstaining?
could you have been abstaining?
could she have been abstaining?
could we have been abstaining?
could you have been abstaining?
could they have been abstaining? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I not abstain?
could you not abstain?
could she not abstain?
could we not abstain?
could you not abstain?
could they not abstain? 	could I not be abstaining?
could you not be abstaining?
could she not be abstaining?
could we not be abstaining?
could you not be abstaining?
could they not be abstaining? 	could I not have abstained?
could you not have abstained?
could she not have abstained?
could we not have abstained?
could you not have abstained?
could they not have abstained? 	could I not have been abstaining?
could you not have been abstaining?
could she not have been abstaining?
could we not have been abstaining?
could you not have been abstaining?
could they not have been abstaining?