English verb conjugation
COULD EXPIRE

Regular verb: expire - expired - expired

Affirmation

Simple form	V-ing form
I could expire you could expire she could expire we could expire you could expire they could expire	I could be expiring you could be expiring she could be expiring we could be expiring you could be expiring they could be expiring
Perfect	V-ing perfect
I could have expired you could have expired she could have expired we could have expired you could have expired they could have expired	I could have been expiring you could have been expiring she could have been expiring we could have been expiring you could have been expiring they could have been expiring

Negation

Simple form	V-ing form
I could not expire you could not expire she could not expire we could not expire you could not expire they could not expire	I could not be expiring you could not be expiring she could not be expiring we could not be expiring you could not be expiring they could not be expiring
Perfect	V-ing perfect
I could not have expired you could not have expired she could not have expired we could not have expired you could not have expired they could not have expired	I could not have been expiring you could not have been expiring she could not have been expiring we could not have been expiring you could not have been expiring they could not have been expiring

Interrogative form

Simple form	V-ing form
could I expire? could you expire? could she expire? could we expire? could you expire? could they expire?	could I be expiring? could you be expiring? could she be expiring? could we be expiring? could you be expiring? could they be expiring?
Perfect	V-ing perfect
could I have expired? could you have expired? could she have expired? could we have expired? could you have expired? could they have expired?	could I have been expiring? could you have been expiring? could she have been expiring? could we have been expiring? could you have been expiring? could they have been expiring?

Interro-negative form

Simple form	V-ing form
could I not expire? could you not expire? could she not expire? could we not expire? could you not expire? could they not expire?	could I not be expiring? could you not be expiring? could she not be expiring? could we not be expiring? could you not be expiring? could they not be expiring?
Perfect	V-ing perfect
could I not have expired? could you not have expired? could she not have expired? could we not have expired? could you not have expired? could they not have expired?	could I not have been expiring? could you not have been expiring? could she not have been expiring? could we not have been expiring? could you not have been expiring? could they not have been expiring?