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