could retain
Verbo regular: retain - retained- retained

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could retain
you could retain
he could retain
we could retain
you could retain
they could retain 	I could be retaining
you could be retaining
he could be retaining
we could be retaining
you could be retaining
they could be retaining	I could have retained
you could have retained
he could have retained
we could have retained
you could have retained
they could have retained	I could have been retaining
you could have been retaining
he could have been retaining
we could have been retaining
you could have been retaining
they could have been retaining	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could not retain
you could not retain
he could not retain
we could not retain
you could not retain
they could not retain 	I could not be retaining
you could not be retaining
he could not be retaining
we could not be retaining
you could not be retaining
they could not be retaining	I could not have retained
you could not have retained
he could not have retained
we could not have retained
you could not have retained
they could not have retained	I could not have been retaining
you could not have been retaining
he could not have been retaining
we could not have been retaining
you could not have been retaining
they could not have been retaining	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I retain?
could you retain?
could he retain?
could we retain?
could you retain?
could they retain? 	could I be retaining?
could you be retaining?
could he be retaining?
could we be retaining?
could you be retaining?
could they be retaining? 	could I have retained?
could you have retained?
could he have retained?
could we have retained?
could you have retained?
could they have retained? 	could I have been retaining?
could you have been retaining?
could he have been retaining?
could we have been retaining?
could you have been retaining?
could they have been retaining? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I not retain?
could you not retain?
could he not retain?
could we not retain?
could you not retain?
could they not retain? 	could I not be retaining?
could you not be retaining?
could he not be retaining?
could we not be retaining?
could you not be retaining?
could they not be retaining? 	could I not have retained?
could you not have retained?
could he not have retained?
could we not have retained?
could you not have retained?
could they not have retained? 	could I not have been retaining?
could you not have been retaining?
could he not have been retaining?
could we not have been retaining?
could you not have been retaining?
could they not have been retaining?