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