could upshift
Verbo regular: upshift - upshifted- upshifted

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could upshift
you could upshift
she could upshift
we could upshift
you could upshift
they could upshift 	I could be upshifting
you could be upshifting
she could be upshifting
we could be upshifting
you could be upshifting
they could be upshifting	I could have upshifted
you could have upshifted
she could have upshifted
we could have upshifted
you could have upshifted
they could have upshifted	I could have been upshifting
you could have been upshifting
she could have been upshifting
we could have been upshifting
you could have been upshifting
they could have been upshifting	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I could not upshift
you could not upshift
she could not upshift
we could not upshift
you could not upshift
they could not upshift 	I could not be upshifting
you could not be upshifting
she could not be upshifting
we could not be upshifting
you could not be upshifting
they could not be upshifting	I could not have upshifted
you could not have upshifted
she could not have upshifted
we could not have upshifted
you could not have upshifted
they could not have upshifted	I could not have been upshifting
you could not have been upshifting
she could not have been upshifting
we could not have been upshifting
you could not have been upshifting
they could not have been upshifting	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I upshift?
could you upshift?
could she upshift?
could we upshift?
could you upshift?
could they upshift? 	could I be upshifting?
could you be upshifting?
could she be upshifting?
could we be upshifting?
could you be upshifting?
could they be upshifting? 	could I have upshifted?
could you have upshifted?
could she have upshifted?
could we have upshifted?
could you have upshifted?
could they have upshifted? 	could I have been upshifting?
could you have been upshifting?
could she have been upshifting?
could we have been upshifting?
could you have been upshifting?
could they have been upshifting? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
could I not upshift?
could you not upshift?
could she not upshift?
could we not upshift?
could you not upshift?
could they not upshift? 	could I not be upshifting?
could you not be upshifting?
could she not be upshifting?
could we not be upshifting?
could you not be upshifting?
could they not be upshifting? 	could I not have upshifted?
could you not have upshifted?
could she not have upshifted?
could we not have upshifted?
could you not have upshifted?
could they not have upshifted? 	could I not have been upshifting?
could you not have been upshifting?
could she not have been upshifting?
could we not have been upshifting?
could you not have been upshifting?
could they not have been upshifting?