should dumb
Regular verb: dumb - dumbed- dumbed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I'd dumb
you'd dumb
she'd dumb
we'd dumb
you'd dumb
they'd dumb 	I'd be dumbing
you'd be dumbing
she'd be dumbing
we'd be dumbing
you'd be dumbing
they'd be dumbing	I should've dumbed
you should've dumbed
she should've dumbed
we should've dumbed
you should've dumbed
they should've dumbed	I should've been dumbing
you should've been dumbing
she should've been dumbing
we should've been dumbing
you should've been dumbing
they should've been dumbing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I shouldn't dumb
you shouldn't dumb
she shouldn't dumb
we shouldn't dumb
you shouldn't dumb
they shouldn't dumb 	I shouldn't be dumbing
you shouldn't be dumbing
she shouldn't be dumbing
we shouldn't be dumbing
you shouldn't be dumbing
they shouldn't be dumbing	I shouldn't have dumbed
you shouldn't have dumbed
she shouldn't have dumbed
we shouldn't have dumbed
you shouldn't have dumbed
they shouldn't have dumbed	I shouldn't have been dumbing
you shouldn't have been dumbing
she shouldn't have been dumbing
we shouldn't have been dumbing
you shouldn't have been dumbing
they shouldn't have been dumbing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
should I dumb?
should you dumb?
should she dumb?
should we dumb?
should you dumb?
should they dumb? 	should I be dumbing?
should you be dumbing?
should she be dumbing?
should we be dumbing?
should you be dumbing?
should they be dumbing? 	should I have dumbed?
should you have dumbed?
should she have dumbed?
should we have dumbed?
should you have dumbed?
should they have dumbed? 	should I have been dumbing?
should you have been dumbing?
should she have been dumbing?
should we have been dumbing?
should you have been dumbing?
should they have been dumbing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
shouldn't I dumb?
shouldn't you dumb?
shouldn't she dumb?
shouldn't we dumb?
shouldn't you dumb?
shouldn't they dumb? 	shouldn't I be dumbing?
shouldn't you be dumbing?
shouldn't she be dumbing?
shouldn't we be dumbing?
shouldn't you be dumbing?
shouldn't they be dumbing? 	shouldn't I have dumbed?
shouldn't you have dumbed?
shouldn't she have dumbed?
shouldn't we have dumbed?
shouldn't you have dumbed?
shouldn't they have dumbed? 	shouldn't I have been dumbing?
shouldn't you have been dumbing?
shouldn't she have been dumbing?
shouldn't we have been dumbing?
shouldn't you have been dumbing?
shouldn't they have been dumbing?