could persevere
Verbo regular: persevere - persevered- persevered

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could persevere
you could persevere
he could persevere
we could persevere
you could persevere
they could persevere 	I could be persevering
you could be persevering
he could be persevering
we could be persevering
you could be persevering
they could be persevering	I could have persevered
you could have persevered
he could have persevered
we could have persevered
you could have persevered
they could have persevered	I could have been persevering
you could have been persevering
he could have been persevering
we could have been persevering
you could have been persevering
they could have been persevering	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could not persevere
you could not persevere
he could not persevere
we could not persevere
you could not persevere
they could not persevere 	I could not be persevering
you could not be persevering
he could not be persevering
we could not be persevering
you could not be persevering
they could not be persevering	I could not have persevered
you could not have persevered
he could not have persevered
we could not have persevered
you could not have persevered
they could not have persevered	I could not have been persevering
you could not have been persevering
he could not have been persevering
we could not have been persevering
you could not have been persevering
they could not have been persevering	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I persevere?
could you persevere?
could he persevere?
could we persevere?
could you persevere?
could they persevere? 	could I be persevering?
could you be persevering?
could he be persevering?
could we be persevering?
could you be persevering?
could they be persevering? 	could I have persevered?
could you have persevered?
could he have persevered?
could we have persevered?
could you have persevered?
could they have persevered? 	could I have been persevering?
could you have been persevering?
could he have been persevering?
could we have been persevering?
could you have been persevering?
could they have been persevering? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I not persevere?
could you not persevere?
could he not persevere?
could we not persevere?
could you not persevere?
could they not persevere? 	could I not be persevering?
could you not be persevering?
could he not be persevering?
could we not be persevering?
could you not be persevering?
could they not be persevering? 	could I not have persevered?
could you not have persevered?
could he not have persevered?
could we not have persevered?
could you not have persevered?
could they not have persevered? 	could I not have been persevering?
could you not have been persevering?
could he not have been persevering?
could we not have been persevering?
could you not have been persevering?
could they not have been persevering?