English verb conjugation
SHOULD CONCERN

Regular verb: concern - concerned - concerned

Affirmation

Simple form	V-ing form
I'd concern you'd concern he'd concern we'd concern you'd concern they'd concern	I'd be concerning you'd be concerning he'd be concerning we'd be concerning you'd be concerning they'd be concerning
Perfect	V-ing perfect
I should've concerned you should've concerned he should've concerned we should've concerned you should've concerned they should've concerned	I should've been concerning you should've been concerning he should've been concerning we should've been concerning you should've been concerning they should've been concerning

Negation

Simple form	V-ing form
I shouldn't concern you shouldn't concern he shouldn't concern we shouldn't concern you shouldn't concern they shouldn't concern	I shouldn't be concerning you shouldn't be concerning he shouldn't be concerning we shouldn't be concerning you shouldn't be concerning they shouldn't be concerning
Perfect	V-ing perfect
I shouldn't have concerned you shouldn't have concerned he shouldn't have concerned we shouldn't have concerned you shouldn't have concerned they shouldn't have concerned	I shouldn't have been concerning you shouldn't have been concerning he shouldn't have been concerning we shouldn't have been concerning you shouldn't have been concerning they shouldn't have been concerning

Interrogative form

Simple form	V-ing form
should I concern? should you concern? should he concern? should we concern? should you concern? should they concern?	should I be concerning? should you be concerning? should he be concerning? should we be concerning? should you be concerning? should they be concerning?
Perfect	V-ing perfect
should I have concerned? should you have concerned? should he have concerned? should we have concerned? should you have concerned? should they have concerned?	should I have been concerning? should you have been concerning? should he have been concerning? should we have been concerning? should you have been concerning? should they have been concerning?

Interro-negative form

Simple form	V-ing form
shouldn't I concern? shouldn't you concern? shouldn't he concern? shouldn't we concern? shouldn't you concern? shouldn't they concern?	shouldn't I be concerning? shouldn't you be concerning? shouldn't he be concerning? shouldn't we be concerning? shouldn't you be concerning? shouldn't they be concerning?
Perfect	V-ing perfect
shouldn't I have concerned? shouldn't you have concerned? shouldn't he have concerned? shouldn't we have concerned? shouldn't you have concerned? shouldn't they have concerned?	shouldn't I have been concerning? shouldn't you have been concerning? shouldn't he have been concerning? shouldn't we have been concerning? shouldn't you have been concerning? shouldn't they have been concerning?