English verb conjugation
MUST FLAP

Regular verb: flap - flapped - flapped

Affirmation

Simple form	V-ing form
I must flap you must flap he must flap we must flap you must flap they must flap	I must be flapping you must be flapping he must be flapping we must be flapping you must be flapping they must be flapping
Perfect	V-ing perfect
I must have flapped you must have flapped he must have flapped we must have flapped you must have flapped they must have flapped	I must have been flapping you must have been flapping he must have been flapping we must have been flapping you must have been flapping they must have been flapping

Negation

Simple form	V-ing form
I mustn't flap you mustn't flap he mustn't flap we mustn't flap you mustn't flap they mustn't flap	I mustn't be flapping you mustn't be flapping he mustn't be flapping we mustn't be flapping you mustn't be flapping they mustn't be flapping
Perfect	V-ing perfect
I mustn't have flapped you mustn't have flapped he mustn't have flapped we mustn't have flapped you mustn't have flapped they mustn't have flapped	I mustn't have been flapping you mustn't have been flapping he mustn't have been flapping we mustn't have been flapping you mustn't have been flapping they mustn't have been flapping

Interrogative form

Simple form	V-ing form
must I flap? must you flap? must he flap? must we flap? must you flap? must they flap?	must I be flapping? must you be flapping? must he be flapping? must we be flapping? must you be flapping? must they be flapping?
Perfect	V-ing perfect
must I have flapped? must you have flapped? must he have flapped? must we have flapped? must you have flapped? must they have flapped?	must I have been flapping? must you have been flapping? must he have been flapping? must we have been flapping? must you have been flapping? must they have been flapping?

Interro-negative form

Simple form	V-ing form
mustn't I flap? mustn't you flap? mustn't he flap? mustn't we flap? mustn't you flap? mustn't they flap?	mustn't I be flapping? mustn't you be flapping? mustn't he be flapping? mustn't we be flapping? mustn't you be flapping? mustn't they be flapping?
Perfect	V-ing perfect
mustn't I have flapped? mustn't you have flapped? mustn't he have flapped? mustn't we have flapped? mustn't you have flapped? mustn't they have flapped?	mustn't I have been flapping? mustn't you have been flapping? mustn't he have been flapping? mustn't we have been flapping? mustn't you have been flapping? mustn't they have been flapping?