could rival
Verbo regular: rival - rivalled- rivalled

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could rival
you could rival
she could rival
we could rival
you could rival
they could rival 	I could be rivalling
you could be rivalling
she could be rivalling
we could be rivalling
you could be rivalling
they could be rivalling	I could have rivalled
you could have rivalled
she could have rivalled
we could have rivalled
you could have rivalled
they could have rivalled	I could have been rivalling
you could have been rivalling
she could have been rivalling
we could have been rivalling
you could have been rivalling
they could have been rivalling	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could not rival
you could not rival
she could not rival
we could not rival
you could not rival
they could not rival 	I could not be rivalling
you could not be rivalling
she could not be rivalling
we could not be rivalling
you could not be rivalling
they could not be rivalling	I could not have rivalled
you could not have rivalled
she could not have rivalled
we could not have rivalled
you could not have rivalled
they could not have rivalled	I could not have been rivalling
you could not have been rivalling
she could not have been rivalling
we could not have been rivalling
you could not have been rivalling
they could not have been rivalling	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I rival?
could you rival?
could she rival?
could we rival?
could you rival?
could they rival? 	could I be rivalling?
could you be rivalling?
could she be rivalling?
could we be rivalling?
could you be rivalling?
could they be rivalling? 	could I have rivalled?
could you have rivalled?
could she have rivalled?
could we have rivalled?
could you have rivalled?
could they have rivalled? 	could I have been rivalling?
could you have been rivalling?
could she have been rivalling?
could we have been rivalling?
could you have been rivalling?
could they have been rivalling? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I not rival?
could you not rival?
could she not rival?
could we not rival?
could you not rival?
could they not rival? 	could I not be rivalling?
could you not be rivalling?
could she not be rivalling?
could we not be rivalling?
could you not be rivalling?
could they not be rivalling? 	could I not have rivalled?
could you not have rivalled?
could she not have rivalled?
could we not have rivalled?
could you not have rivalled?
could they not have rivalled? 	could I not have been rivalling?
could you not have been rivalling?
could she not have been rivalling?
could we not have been rivalling?
could you not have been rivalling?
could they not have been rivalling?