English verb conjugation
COULD SERVE

Regular verb: serve - served - served

Affirmation

Simple form	V-ing form
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
Perfect	V-ing perfect
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

Negation

Simple form	V-ing form
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
Perfect	V-ing perfect
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

Interrogative form

Simple form	V-ing form
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?
Perfect	V-ing perfect
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?

Interro-negative form

Simple form	V-ing form
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?
Perfect	V-ing perfect
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?