could backcross
Verbo regular: backcross - backcrossed- backcrossed

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could backcross
you could backcross
he could backcross
we could backcross
you could backcross
they could backcross 	I could be backcrossing
you could be backcrossing
he could be backcrossing
we could be backcrossing
you could be backcrossing
they could be backcrossing	I could have backcrossed
you could have backcrossed
he could have backcrossed
we could have backcrossed
you could have backcrossed
they could have backcrossed	I could have been backcrossing
you could have been backcrossing
he could have been backcrossing
we could have been backcrossing
you could have been backcrossing
they could have been backcrossing	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could not backcross
you could not backcross
he could not backcross
we could not backcross
you could not backcross
they could not backcross 	I could not be backcrossing
you could not be backcrossing
he could not be backcrossing
we could not be backcrossing
you could not be backcrossing
they could not be backcrossing	I could not have backcrossed
you could not have backcrossed
he could not have backcrossed
we could not have backcrossed
you could not have backcrossed
they could not have backcrossed	I could not have been backcrossing
you could not have been backcrossing
he could not have been backcrossing
we could not have been backcrossing
you could not have been backcrossing
they could not have been backcrossing	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I backcross?
could you backcross?
could he backcross?
could we backcross?
could you backcross?
could they backcross? 	could I be backcrossing?
could you be backcrossing?
could he be backcrossing?
could we be backcrossing?
could you be backcrossing?
could they be backcrossing? 	could I have backcrossed?
could you have backcrossed?
could he have backcrossed?
could we have backcrossed?
could you have backcrossed?
could they have backcrossed? 	could I have been backcrossing?
could you have been backcrossing?
could he have been backcrossing?
could we have been backcrossing?
could you have been backcrossing?
could they have been backcrossing? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I not backcross?
could you not backcross?
could he not backcross?
could we not backcross?
could you not backcross?
could they not backcross? 	could I not be backcrossing?
could you not be backcrossing?
could he not be backcrossing?
could we not be backcrossing?
could you not be backcrossing?
could they not be backcrossing? 	could I not have backcrossed?
could you not have backcrossed?
could he not have backcrossed?
could we not have backcrossed?
could you not have backcrossed?
could they not have backcrossed? 	could I not have been backcrossing?
could you not have been backcrossing?
could he not have been backcrossing?
could we not have been backcrossing?
could you not have been backcrossing?
could they not have been backcrossing?