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