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