could preexchange
Verbo regular: preexchange - preexchanged- preexchanged

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could preexchange
you could preexchange
he could preexchange
we could preexchange
you could preexchange
they could preexchange 	I could be preexchanging
you could be preexchanging
he could be preexchanging
we could be preexchanging
you could be preexchanging
they could be preexchanging	I could have preexchanged
you could have preexchanged
he could have preexchanged
we could have preexchanged
you could have preexchanged
they could have preexchanged	I could have been preexchanging
you could have been preexchanging
he could have been preexchanging
we could have been preexchanging
you could have been preexchanging
they could have been preexchanging	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could not preexchange
you could not preexchange
he could not preexchange
we could not preexchange
you could not preexchange
they could not preexchange 	I could not be preexchanging
you could not be preexchanging
he could not be preexchanging
we could not be preexchanging
you could not be preexchanging
they could not be preexchanging	I could not have preexchanged
you could not have preexchanged
he could not have preexchanged
we could not have preexchanged
you could not have preexchanged
they could not have preexchanged	I could not have been preexchanging
you could not have been preexchanging
he could not have been preexchanging
we could not have been preexchanging
you could not have been preexchanging
they could not have been preexchanging	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I preexchange?
could you preexchange?
could he preexchange?
could we preexchange?
could you preexchange?
could they preexchange? 	could I be preexchanging?
could you be preexchanging?
could he be preexchanging?
could we be preexchanging?
could you be preexchanging?
could they be preexchanging? 	could I have preexchanged?
could you have preexchanged?
could he have preexchanged?
could we have preexchanged?
could you have preexchanged?
could they have preexchanged? 	could I have been preexchanging?
could you have been preexchanging?
could he have been preexchanging?
could we have been preexchanging?
could you have been preexchanging?
could they have been preexchanging? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I not preexchange?
could you not preexchange?
could he not preexchange?
could we not preexchange?
could you not preexchange?
could they not preexchange? 	could I not be preexchanging?
could you not be preexchanging?
could he not be preexchanging?
could we not be preexchanging?
could you not be preexchanging?
could they not be preexchanging? 	could I not have preexchanged?
could you not have preexchanged?
could he not have preexchanged?
could we not have preexchanged?
could you not have preexchanged?
could they not have preexchanged? 	could I not have been preexchanging?
could you not have been preexchanging?
could he not have been preexchanging?
could we not have been preexchanging?
could you not have been preexchanging?
could they not have been preexchanging?