could serve
Verbo regular: serve - served- served

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could serve
you could serve
he could serve
we could serve
you could serve
they could serve 	I could be serving
you could be serving
he could be serving
we could be serving
you could be serving
they could be serving	I could have served
you could have served
he could have served
we could have served
you could have served
they could have served	I could have been serving
you could have been serving
he could have been serving
we could have been serving
you could have been serving
they could have been serving	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I could not serve
you could not serve
he could not serve
we could not serve
you could not serve
they could not serve 	I could not be serving
you could not be serving
he could not be serving
we could not be serving
you could not be serving
they could not be serving	I could not have served
you could not have served
he could not have served
we could not have served
you could not have served
they could not have served	I could not have been serving
you could not have been serving
he could not have been serving
we could not have been serving
you could not have been serving
they could not have been serving	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I serve?
could you serve?
could he serve?
could we serve?
could you serve?
could they serve? 	could I be serving?
could you be serving?
could he be serving?
could we be serving?
could you be serving?
could they be serving? 	could I have served?
could you have served?
could he have served?
could we have served?
could you have served?
could they have served? 	could I have been serving?
could you have been serving?
could he have been serving?
could we have been serving?
could you have been serving?
could they have been serving? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
could I not serve?
could you not serve?
could he not serve?
could we not serve?
could you not serve?
could they not serve? 	could I not be serving?
could you not be serving?
could he not be serving?
could we not be serving?
could you not be serving?
could they not be serving? 	could I not have served?
could you not have served?
could he not have served?
could we not have served?
could you not have served?
could they not have served? 	could I not have been serving?
could you not have been serving?
could he not have been serving?
could we not have been serving?
could you not have been serving?
could they not have been serving?