English verb conjugation
SHOULD EXIST

Regular verb: exist - existed - existed

Affirmation

Simple form	V-ing form
I'd exist you'd exist he'd exist we'd exist you'd exist they'd exist	I'd be existing you'd be existing he'd be existing we'd be existing you'd be existing they'd be existing
Perfect	V-ing perfect
I should've existed you should've existed he should've existed we should've existed you should've existed they should've existed	I should've been existing you should've been existing he should've been existing we should've been existing you should've been existing they should've been existing

Negation

Simple form	V-ing form
I shouldn't exist you shouldn't exist he shouldn't exist we shouldn't exist you shouldn't exist they shouldn't exist	I shouldn't be existing you shouldn't be existing he shouldn't be existing we shouldn't be existing you shouldn't be existing they shouldn't be existing
Perfect	V-ing perfect
I shouldn't have existed you shouldn't have existed he shouldn't have existed we shouldn't have existed you shouldn't have existed they shouldn't have existed	I shouldn't have been existing you shouldn't have been existing he shouldn't have been existing we shouldn't have been existing you shouldn't have been existing they shouldn't have been existing

Interrogative form

Simple form	V-ing form
should I exist? should you exist? should he exist? should we exist? should you exist? should they exist?	should I be existing? should you be existing? should he be existing? should we be existing? should you be existing? should they be existing?
Perfect	V-ing perfect
should I have existed? should you have existed? should he have existed? should we have existed? should you have existed? should they have existed?	should I have been existing? should you have been existing? should he have been existing? should we have been existing? should you have been existing? should they have been existing?

Interro-negative form

Simple form	V-ing form
shouldn't I exist? shouldn't you exist? shouldn't he exist? shouldn't we exist? shouldn't you exist? shouldn't they exist?	shouldn't I be existing? shouldn't you be existing? shouldn't he be existing? shouldn't we be existing? shouldn't you be existing? shouldn't they be existing?
Perfect	V-ing perfect
shouldn't I have existed? shouldn't you have existed? shouldn't he have existed? shouldn't we have existed? shouldn't you have existed? shouldn't they have existed?	shouldn't I have been existing? shouldn't you have been existing? shouldn't he have been existing? shouldn't we have been existing? shouldn't you have been existing? shouldn't they have been existing?