English verb conjugation
MUST FLAIL

Regular verb: flail - flailed - flailed

Affirmation

Simple form	V-ing form
I must flail you must flail he must flail we must flail you must flail they must flail	I must be flailing you must be flailing he must be flailing we must be flailing you must be flailing they must be flailing
Perfect	V-ing perfect
I must have flailed you must have flailed he must have flailed we must have flailed you must have flailed they must have flailed	I must have been flailing you must have been flailing he must have been flailing we must have been flailing you must have been flailing they must have been flailing

Negation

Simple form	V-ing form
I mustn't flail you mustn't flail he mustn't flail we mustn't flail you mustn't flail they mustn't flail	I mustn't be flailing you mustn't be flailing he mustn't be flailing we mustn't be flailing you mustn't be flailing they mustn't be flailing
Perfect	V-ing perfect
I mustn't have flailed you mustn't have flailed he mustn't have flailed we mustn't have flailed you mustn't have flailed they mustn't have flailed	I mustn't have been flailing you mustn't have been flailing he mustn't have been flailing we mustn't have been flailing you mustn't have been flailing they mustn't have been flailing

Interrogative form

Simple form	V-ing form
must I flail? must you flail? must he flail? must we flail? must you flail? must they flail?	must I be flailing? must you be flailing? must he be flailing? must we be flailing? must you be flailing? must they be flailing?
Perfect	V-ing perfect
must I have flailed? must you have flailed? must he have flailed? must we have flailed? must you have flailed? must they have flailed?	must I have been flailing? must you have been flailing? must he have been flailing? must we have been flailing? must you have been flailing? must they have been flailing?

Interro-negative form

Simple form	V-ing form
mustn't I flail? mustn't you flail? mustn't he flail? mustn't we flail? mustn't you flail? mustn't they flail?	mustn't I be flailing? mustn't you be flailing? mustn't he be flailing? mustn't we be flailing? mustn't you be flailing? mustn't they be flailing?
Perfect	V-ing perfect
mustn't I have flailed? mustn't you have flailed? mustn't he have flailed? mustn't we have flailed? mustn't you have flailed? mustn't they have flailed?	mustn't I have been flailing? mustn't you have been flailing? mustn't he have been flailing? mustn't we have been flailing? mustn't you have been flailing? mustn't they have been flailing?