could downshift
Verbo regular: downshift - downshifted- downshifted

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could downshift
you could downshift
she could downshift
we could downshift
you could downshift
they could downshift 	I could be downshifting
you could be downshifting
she could be downshifting
we could be downshifting
you could be downshifting
they could be downshifting	I could have downshifted
you could have downshifted
she could have downshifted
we could have downshifted
you could have downshifted
they could have downshifted	I could have been downshifting
you could have been downshifting
she could have been downshifting
we could have been downshifting
you could have been downshifting
they could have been downshifting	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could not downshift
you could not downshift
she could not downshift
we could not downshift
you could not downshift
they could not downshift 	I could not be downshifting
you could not be downshifting
she could not be downshifting
we could not be downshifting
you could not be downshifting
they could not be downshifting	I could not have downshifted
you could not have downshifted
she could not have downshifted
we could not have downshifted
you could not have downshifted
they could not have downshifted	I could not have been downshifting
you could not have been downshifting
she could not have been downshifting
we could not have been downshifting
you could not have been downshifting
they could not have been downshifting	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I downshift?
could you downshift?
could she downshift?
could we downshift?
could you downshift?
could they downshift? 	could I be downshifting?
could you be downshifting?
could she be downshifting?
could we be downshifting?
could you be downshifting?
could they be downshifting? 	could I have downshifted?
could you have downshifted?
could she have downshifted?
could we have downshifted?
could you have downshifted?
could they have downshifted? 	could I have been downshifting?
could you have been downshifting?
could she have been downshifting?
could we have been downshifting?
could you have been downshifting?
could they have been downshifting? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I not downshift?
could you not downshift?
could she not downshift?
could we not downshift?
could you not downshift?
could they not downshift? 	could I not be downshifting?
could you not be downshifting?
could she not be downshifting?
could we not be downshifting?
could you not be downshifting?
could they not be downshifting? 	could I not have downshifted?
could you not have downshifted?
could she not have downshifted?
could we not have downshifted?
could you not have downshifted?
could they not have downshifted? 	could I not have been downshifting?
could you not have been downshifting?
could she not have been downshifting?
could we not have been downshifting?
could you not have been downshifting?
could they not have been downshifting?