I'd be regreting you'd be regreting he'd be regreting we'd be regreting you'd be regreting they'd be regreting
Perfect
I should've regreted you should've regreted he should've regreted we should've regreted you should've regreted they should've regreted
V-ing perfect
I should've been regreting you should've been regreting he should've been regreting we should've been regreting you should've been regreting they should've been regreting
Negation
Simple form
I shouldn't regret you shouldn't regret he shouldn't regret we shouldn't regret you shouldn't regret they shouldn't regret
V-ing form
I shouldn't be regreting you shouldn't be regreting he shouldn't be regreting we shouldn't be regreting you shouldn't be regreting they shouldn't be regreting
Perfect
I shouldn't have regreted you shouldn't have regreted he shouldn't have regreted we shouldn't have regreted you shouldn't have regreted they shouldn't have regreted
V-ing perfect
I shouldn't have been regreting you shouldn't have been regreting he shouldn't have been regreting we shouldn't have been regreting you shouldn't have been regreting they shouldn't have been regreting
Interrogative form
Simple form
should I regret? should you regret? should he regret? should we regret? should you regret? should they regret?
V-ing form
should I be regreting? should you be regreting? should he be regreting? should we be regreting? should you be regreting? should they be regreting?
Perfect
should I have regreted? should you have regreted? should he have regreted? should we have regreted? should you have regreted? should they have regreted?
V-ing perfect
should I have been regreting? should you have been regreting? should he have been regreting? should we have been regreting? should you have been regreting? should they have been regreting?
Interro-negative form
Simple form
shouldn't I regret? shouldn't you regret? shouldn't he regret? shouldn't we regret? shouldn't you regret? shouldn't they regret?
V-ing form
shouldn't I be regreting? shouldn't you be regreting? shouldn't he be regreting? shouldn't we be regreting? shouldn't you be regreting? shouldn't they be regreting?
Perfect
shouldn't I have regreted? shouldn't you have regreted? shouldn't he have regreted? shouldn't we have regreted? shouldn't you have regreted? shouldn't they have regreted?
V-ing perfect
shouldn't I have been regreting? shouldn't you have been regreting? shouldn't he have been regreting? shouldn't we have been regreting? shouldn't you have been regreting? shouldn't they have been regreting?