I'd be substituting you'd be substituting she'd be substituting we'd be substituting you'd be substituting they'd be substituting
Perfect
I should've substituted you should've substituted she should've substituted we should've substituted you should've substituted they should've substituted
V-ing perfect
I should've been substituting you should've been substituting she should've been substituting we should've been substituting you should've been substituting they should've been substituting
Negation
Simple form
I shouldn't substitute you shouldn't substitute she shouldn't substitute we shouldn't substitute you shouldn't substitute they shouldn't substitute
V-ing form
I shouldn't be substituting you shouldn't be substituting she shouldn't be substituting we shouldn't be substituting you shouldn't be substituting they shouldn't be substituting
Perfect
I shouldn't have substituted you shouldn't have substituted she shouldn't have substituted we shouldn't have substituted you shouldn't have substituted they shouldn't have substituted
V-ing perfect
I shouldn't have been substituting you shouldn't have been substituting she shouldn't have been substituting we shouldn't have been substituting you shouldn't have been substituting they shouldn't have been substituting
Interrogative form
Simple form
should I substitute? should you substitute? should she substitute? should we substitute? should you substitute? should they substitute?
V-ing form
should I be substituting? should you be substituting? should she be substituting? should we be substituting? should you be substituting? should they be substituting?
Perfect
should I have substituted? should you have substituted? should she have substituted? should we have substituted? should you have substituted? should they have substituted?
V-ing perfect
should I have been substituting? should you have been substituting? should she have been substituting? should we have been substituting? should you have been substituting? should they have been substituting?
Interro-negative form
Simple form
shouldn't I substitute? shouldn't you substitute? shouldn't she substitute? shouldn't we substitute? shouldn't you substitute? shouldn't they substitute?
V-ing form
shouldn't I be substituting? shouldn't you be substituting? shouldn't she be substituting? shouldn't we be substituting? shouldn't you be substituting? shouldn't they be substituting?
Perfect
shouldn't I have substituted? shouldn't you have substituted? shouldn't she have substituted? shouldn't we have substituted? shouldn't you have substituted? shouldn't they have substituted?
V-ing perfect
shouldn't I have been substituting? shouldn't you have been substituting? shouldn't she have been substituting? shouldn't we have been substituting? shouldn't you have been substituting? shouldn't they have been substituting?