I'd be concerning you'd be concerning she'd be concerning we'd be concerning you'd be concerning they'd be concerning
Perfect
I should've concerned you should've concerned she should've concerned we should've concerned you should've concerned they should've concerned
V-ing perfect
I should've been concerning you should've been concerning she should've been concerning we should've been concerning you should've been concerning they should've been concerning
Negation
Simple form
I shouldn't concern you shouldn't concern she shouldn't concern we shouldn't concern you shouldn't concern they shouldn't concern
V-ing form
I shouldn't be concerning you shouldn't be concerning she shouldn't be concerning we shouldn't be concerning you shouldn't be concerning they shouldn't be concerning
Perfect
I shouldn't have concerned you shouldn't have concerned she shouldn't have concerned we shouldn't have concerned you shouldn't have concerned they shouldn't have concerned
V-ing perfect
I shouldn't have been concerning you shouldn't have been concerning she 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
should I concern? should you concern? should she concern? should we concern? should you concern? should they concern?
V-ing form
should I be concerning? should you be concerning? should she be concerning? should we be concerning? should you be concerning? should they be concerning?
Perfect
should I have concerned? should you have concerned? should she have concerned? should we have concerned? should you have concerned? should they have concerned?
V-ing perfect
should I have been concerning? should you have been concerning? should she have been concerning? should we have been concerning? should you have been concerning? should they have been concerning?
Interro-negative form
Simple form
shouldn't I concern? shouldn't you concern? shouldn't she concern? shouldn't we concern? shouldn't you concern? shouldn't they concern?
V-ing form
shouldn't I be concerning? shouldn't you be concerning? shouldn't she be concerning? shouldn't we be concerning? shouldn't you be concerning? shouldn't they be concerning?
Perfect
shouldn't I have concerned? shouldn't you have concerned? shouldn't she have concerned? shouldn't we have concerned? shouldn't you have concerned? shouldn't they have concerned?
V-ing perfect
shouldn't I have been concerning? shouldn't you have been concerning? shouldn't she have been concerning? shouldn't we have been concerning? shouldn't you have been concerning? shouldn't they have been concerning?