English verb conjugation
COULD UMPIRE

Regular verb: umpire - umpired - umpired

Affirmation

Simple form	V-ing form
I could umpire you could umpire he could umpire we could umpire you could umpire they could umpire	I could be umpiring you could be umpiring he could be umpiring we could be umpiring you could be umpiring they could be umpiring
Perfect	V-ing perfect
I could have umpired you could have umpired he could have umpired we could have umpired you could have umpired they could have umpired	I could have been umpiring you could have been umpiring he could have been umpiring we could have been umpiring you could have been umpiring they could have been umpiring

Negation

Simple form	V-ing form
I could not umpire you could not umpire he could not umpire we could not umpire you could not umpire they could not umpire	I could not be umpiring you could not be umpiring he could not be umpiring we could not be umpiring you could not be umpiring they could not be umpiring
Perfect	V-ing perfect
I could not have umpired you could not have umpired he could not have umpired we could not have umpired you could not have umpired they could not have umpired	I could not have been umpiring you could not have been umpiring he could not have been umpiring we could not have been umpiring you could not have been umpiring they could not have been umpiring

Interrogative form

Simple form	V-ing form
could I umpire? could you umpire? could he umpire? could we umpire? could you umpire? could they umpire?	could I be umpiring? could you be umpiring? could he be umpiring? could we be umpiring? could you be umpiring? could they be umpiring?
Perfect	V-ing perfect
could I have umpired? could you have umpired? could he have umpired? could we have umpired? could you have umpired? could they have umpired?	could I have been umpiring? could you have been umpiring? could he have been umpiring? could we have been umpiring? could you have been umpiring? could they have been umpiring?

Interro-negative form

Simple form	V-ing form
could I not umpire? could you not umpire? could he not umpire? could we not umpire? could you not umpire? could they not umpire?	could I not be umpiring? could you not be umpiring? could he not be umpiring? could we not be umpiring? could you not be umpiring? could they not be umpiring?
Perfect	V-ing perfect
could I not have umpired? could you not have umpired? could he not have umpired? could we not have umpired? could you not have umpired? could they not have umpired?	could I not have been umpiring? could you not have been umpiring? could he not have been umpiring? could we not have been umpiring? could you not have been umpiring? could they not have been umpiring?