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