should retard
Regular verb: retard - retarded- retarded

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I'd retard
you'd retard
she'd retard
we'd retard
you'd retard
they'd retard 	I'd be retarding
you'd be retarding
she'd be retarding
we'd be retarding
you'd be retarding
they'd be retarding	I should've retarded
you should've retarded
she should've retarded
we should've retarded
you should've retarded
they should've retarded	I should've been retarding
you should've been retarding
she should've been retarding
we should've been retarding
you should've been retarding
they should've been retarding	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I shouldn't retard
you shouldn't retard
she shouldn't retard
we shouldn't retard
you shouldn't retard
they shouldn't retard 	I shouldn't be retarding
you shouldn't be retarding
she shouldn't be retarding
we shouldn't be retarding
you shouldn't be retarding
they shouldn't be retarding	I shouldn't have retarded
you shouldn't have retarded
she shouldn't have retarded
we shouldn't have retarded
you shouldn't have retarded
they shouldn't have retarded	I shouldn't have been retarding
you shouldn't have been retarding
she shouldn't have been retarding
we shouldn't have been retarding
you shouldn't have been retarding
they shouldn't have been retarding	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
should I retard?
should you retard?
should she retard?
should we retard?
should you retard?
should they retard? 	should I be retarding?
should you be retarding?
should she be retarding?
should we be retarding?
should you be retarding?
should they be retarding? 	should I have retarded?
should you have retarded?
should she have retarded?
should we have retarded?
should you have retarded?
should they have retarded? 	should I have been retarding?
should you have been retarding?
should she have been retarding?
should we have been retarding?
should you have been retarding?
should they have been retarding? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
shouldn't I retard?
shouldn't you retard?
shouldn't she retard?
shouldn't we retard?
shouldn't you retard?
shouldn't they retard? 	shouldn't I be retarding?
shouldn't you be retarding?
shouldn't she be retarding?
shouldn't we be retarding?
shouldn't you be retarding?
shouldn't they be retarding? 	shouldn't I have retarded?
shouldn't you have retarded?
shouldn't she have retarded?
shouldn't we have retarded?
shouldn't you have retarded?
shouldn't they have retarded? 	shouldn't I have been retarding?
shouldn't you have been retarding?
shouldn't she have been retarding?
shouldn't we have been retarding?
shouldn't you have been retarding?
shouldn't they have been retarding?