English verb conjugation
MUST REGAIN

Regular verb: regain - regained - regained

Affirmation

Simple form	V-ing form
I must regain you must regain she must regain we must regain you must regain they must regain	I must be regaining you must be regaining she must be regaining we must be regaining you must be regaining they must be regaining
Perfect	V-ing perfect
I must have regained you must have regained she must have regained we must have regained you must have regained they must have regained	I must have been regaining you must have been regaining she must have been regaining we must have been regaining you must have been regaining they must have been regaining

Negation

Simple form	V-ing form
I mustn't regain you mustn't regain she mustn't regain we mustn't regain you mustn't regain they mustn't regain	I mustn't be regaining you mustn't be regaining she mustn't be regaining we mustn't be regaining you mustn't be regaining they mustn't be regaining
Perfect	V-ing perfect
I mustn't have regained you mustn't have regained she mustn't have regained we mustn't have regained you mustn't have regained they mustn't have regained	I mustn't have been regaining you mustn't have been regaining she mustn't have been regaining we mustn't have been regaining you mustn't have been regaining they mustn't have been regaining

Interrogative form

Simple form	V-ing form
must I regain? must you regain? must she regain? must we regain? must you regain? must they regain?	must I be regaining? must you be regaining? must she be regaining? must we be regaining? must you be regaining? must they be regaining?
Perfect	V-ing perfect
must I have regained? must you have regained? must she have regained? must we have regained? must you have regained? must they have regained?	must I have been regaining? must you have been regaining? must she have been regaining? must we have been regaining? must you have been regaining? must they have been regaining?

Interro-negative form

Simple form	V-ing form
mustn't I regain? mustn't you regain? mustn't she regain? mustn't we regain? mustn't you regain? mustn't they regain?	mustn't I be regaining? mustn't you be regaining? mustn't she be regaining? mustn't we be regaining? mustn't you be regaining? mustn't they be regaining?
Perfect	V-ing perfect
mustn't I have regained? mustn't you have regained? mustn't she have regained? mustn't we have regained? mustn't you have regained? mustn't they have regained?	mustn't I have been regaining? mustn't you have been regaining? mustn't she have been regaining? mustn't we have been regaining? mustn't you have been regaining? mustn't they have been regaining?