could modulate
Verbo regular: modulate - modulated- modulated

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could modulate
you could modulate
she could modulate
we could modulate
you could modulate
they could modulate 	I could be modulating
you could be modulating
she could be modulating
we could be modulating
you could be modulating
they could be modulating	I could have modulated
you could have modulated
she could have modulated
we could have modulated
you could have modulated
they could have modulated	I could have been modulating
you could have been modulating
she could have been modulating
we could have been modulating
you could have been modulating
they could have been modulating	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could not modulate
you could not modulate
she could not modulate
we could not modulate
you could not modulate
they could not modulate 	I could not be modulating
you could not be modulating
she could not be modulating
we could not be modulating
you could not be modulating
they could not be modulating	I could not have modulated
you could not have modulated
she could not have modulated
we could not have modulated
you could not have modulated
they could not have modulated	I could not have been modulating
you could not have been modulating
she could not have been modulating
we could not have been modulating
you could not have been modulating
they could not have been modulating	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I modulate?
could you modulate?
could she modulate?
could we modulate?
could you modulate?
could they modulate? 	could I be modulating?
could you be modulating?
could she be modulating?
could we be modulating?
could you be modulating?
could they be modulating? 	could I have modulated?
could you have modulated?
could she have modulated?
could we have modulated?
could you have modulated?
could they have modulated? 	could I have been modulating?
could you have been modulating?
could she have been modulating?
could we have been modulating?
could you have been modulating?
could they have been modulating? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I not modulate?
could you not modulate?
could she not modulate?
could we not modulate?
could you not modulate?
could they not modulate? 	could I not be modulating?
could you not be modulating?
could she not be modulating?
could we not be modulating?
could you not be modulating?
could they not be modulating? 	could I not have modulated?
could you not have modulated?
could she not have modulated?
could we not have modulated?
could you not have modulated?
could they not have modulated? 	could I not have been modulating?
could you not have been modulating?
could she not have been modulating?
could we not have been modulating?
could you not have been modulating?
could they not have been modulating?