can retrograde
Regular verb: retrograde - retrograded- retrograded

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

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can't retrograde
you can't retrograde
she can't retrograde
we can't retrograde
you can't retrograde
they can't retrograde 	I can't be retrograding
you can't be retrograding
she can't be retrograding
we can't be retrograding
you can't be retrograding
they can't be retrograding	I can't have retrograded
you can't have retrograded
she can't have retrograded
we can't have retrograded
you can't have retrograded
they can't have retrograded	I can't have been retrograding
you can't have been retrograding
she can't have been retrograding
we can't have been retrograding
you can't have been retrograding
they can't have been retrograding	

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

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