English verb conjugation
MUST RETROGRADE

Regular verb: retrograde - retrograded - retrograded

Affirmation

Simple form	V-ing form
I must retrograde you must retrograde he must retrograde we must retrograde you must retrograde they must retrograde	I must be retrograding you must be retrograding he must be retrograding we must be retrograding you must be retrograding they must be retrograding
Perfect	V-ing perfect
I must have retrograded you must have retrograded he must have retrograded we must have retrograded you must have retrograded they must have retrograded	I must have been retrograding you must have been retrograding he must have been retrograding we must have been retrograding you must have been retrograding they must have been retrograding

Negation

Simple form	V-ing form
I mustn't retrograde you mustn't retrograde he mustn't retrograde we mustn't retrograde you mustn't retrograde they mustn't retrograde	I mustn't be retrograding you mustn't be retrograding he mustn't be retrograding we mustn't be retrograding you mustn't be retrograding they mustn't be retrograding
Perfect	V-ing perfect
I mustn't have retrograded you mustn't have retrograded he mustn't have retrograded we mustn't have retrograded you mustn't have retrograded they mustn't have retrograded	I mustn't have been retrograding you mustn't have been retrograding he mustn't have been retrograding we mustn't have been retrograding you mustn't have been retrograding they mustn't have been retrograding

Interrogative form

Simple form	V-ing form
must I retrograde? must you retrograde? must he retrograde? must we retrograde? must you retrograde? must they retrograde?	must I be retrograding? must you be retrograding? must he be retrograding? must we be retrograding? must you be retrograding? must they be retrograding?
Perfect	V-ing perfect
must I have retrograded? must you have retrograded? must he have retrograded? must we have retrograded? must you have retrograded? must they have retrograded?	must I have been retrograding? must you have been retrograding? must he have been retrograding? must we have been retrograding? must you have been retrograding? must they have been retrograding?

Interro-negative form

Simple form	V-ing form
mustn't I retrograde? mustn't you retrograde? mustn't he retrograde? mustn't we retrograde? mustn't you retrograde? mustn't they retrograde?	mustn't I be retrograding? mustn't you be retrograding? mustn't he be retrograding? mustn't we be retrograding? mustn't you be retrograding? mustn't they be retrograding?
Perfect	V-ing perfect
mustn't I have retrograded? mustn't you have retrograded? mustn't he have retrograded? mustn't we have retrograded? mustn't you have retrograded? mustn't they have retrograded?	mustn't I have been retrograding? mustn't you have been retrograding? mustn't he have been retrograding? mustn't we have been retrograding? mustn't you have been retrograding? mustn't they have been retrograding?