should retrograde
Regular verb: retrograde - retrograded- retrograded

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I should retrograde
you should retrograde
she should retrograde
we should retrograde
you should retrograde
they should retrograde 	I should be retrograding
you should be retrograding
she should be retrograding
we should be retrograding
you should be retrograding
they should be retrograding	I should have retrograded
you should have retrograded
she should have retrograded
we should have retrograded
you should have retrograded
they should have retrograded	I should have been retrograding
you should have been retrograding
she should have been retrograding
we should have been retrograding
you should have been retrograding
they should have been retrograding	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I should not retrograde
you should not retrograde
she should not retrograde
we should not retrograde
you should not retrograde
they should not retrograde 	I should not be retrograding
you should not be retrograding
she should not be retrograding
we should not be retrograding
you should not be retrograding
they should not be retrograding	I should not have retrograded
you should not have retrograded
she should not have retrograded
we should not have retrograded
you should not have retrograded
they should not have retrograded	I should not have been retrograding
you should not have been retrograding
she should not have been retrograding
we should not have been retrograding
you should not have been retrograding
they should not have been retrograding	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
should I retrograde?
should you retrograde?
should she retrograde?
should we retrograde?
should you retrograde?
should they retrograde? 	should I be retrograding?
should you be retrograding?
should she be retrograding?
should we be retrograding?
should you be retrograding?
should they be retrograding? 	should I have retrograded?
should you have retrograded?
should she have retrograded?
should we have retrograded?
should you have retrograded?
should they have retrograded? 	should I have been retrograding?
should you have been retrograding?
should she have been retrograding?
should we have been retrograding?
should you have been retrograding?
should they have been retrograding? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
should I not retrograde?
should you not retrograde?
should she not retrograde?
should we not retrograde?
should you not retrograde?
should they not retrograde? 	should I not be retrograding?
should you not be retrograding?
should she not be retrograding?
should we not be retrograding?
should you not be retrograding?
should they not be retrograding? 	should I not have retrograded?
should you not have retrograded?
should she not have retrograded?
should we not have retrograded?
should you not have retrograded?
should they not have retrograded? 	should I not have been retrograding?
should you not have been retrograding?
should she not have been retrograding?
should we not have been retrograding?
should you not have been retrograding?
should they not have been retrograding?