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