English verb conjugation
COULD PREEXIST

Regular verb: preexist - preexisted - preexisted

Affirmation

Simple form	V-ing form
I could preexist you could preexist he could preexist we could preexist you could preexist they could preexist	I could be preexisting you could be preexisting he could be preexisting we could be preexisting you could be preexisting they could be preexisting
Perfect	V-ing perfect
I could have preexisted you could have preexisted he could have preexisted we could have preexisted you could have preexisted they could have preexisted	I could have been preexisting you could have been preexisting he could have been preexisting we could have been preexisting you could have been preexisting they could have been preexisting

Negation

Simple form	V-ing form
I could not preexist you could not preexist he could not preexist we could not preexist you could not preexist they could not preexist	I could not be preexisting you could not be preexisting he could not be preexisting we could not be preexisting you could not be preexisting they could not be preexisting
Perfect	V-ing perfect
I could not have preexisted you could not have preexisted he could not have preexisted we could not have preexisted you could not have preexisted they could not have preexisted	I could not have been preexisting you could not have been preexisting he could not have been preexisting we could not have been preexisting you could not have been preexisting they could not have been preexisting

Interrogative form

Simple form	V-ing form
could I preexist? could you preexist? could he preexist? could we preexist? could you preexist? could they preexist?	could I be preexisting? could you be preexisting? could he be preexisting? could we be preexisting? could you be preexisting? could they be preexisting?
Perfect	V-ing perfect
could I have preexisted? could you have preexisted? could he have preexisted? could we have preexisted? could you have preexisted? could they have preexisted?	could I have been preexisting? could you have been preexisting? could he have been preexisting? could we have been preexisting? could you have been preexisting? could they have been preexisting?

Interro-negative form

Simple form	V-ing form
could I not preexist? could you not preexist? could he not preexist? could we not preexist? could you not preexist? could they not preexist?	could I not be preexisting? could you not be preexisting? could he not be preexisting? could we not be preexisting? could you not be preexisting? could they not be preexisting?
Perfect	V-ing perfect
could I not have preexisted? could you not have preexisted? could he not have preexisted? could we not have preexisted? could you not have preexisted? could they not have preexisted?	could I not have been preexisting? could you not have been preexisting? could he not have been preexisting? could we not have been preexisting? could you not have been preexisting? could they not have been preexisting?