English verb conjugation
MUST KNUCKLE

Regular verb: knuckle - knuckled - knuckled

Affirmation

Simple form	V-ing form
I must knuckle you must knuckle he must knuckle we must knuckle you must knuckle they must knuckle	I must be knuckling you must be knuckling he must be knuckling we must be knuckling you must be knuckling they must be knuckling
Perfect	V-ing perfect
I must have knuckled you must have knuckled he must have knuckled we must have knuckled you must have knuckled they must have knuckled	I must have been knuckling you must have been knuckling he must have been knuckling we must have been knuckling you must have been knuckling they must have been knuckling

Negation

Simple form	V-ing form
I mustn't knuckle you mustn't knuckle he mustn't knuckle we mustn't knuckle you mustn't knuckle they mustn't knuckle	I mustn't be knuckling you mustn't be knuckling he mustn't be knuckling we mustn't be knuckling you mustn't be knuckling they mustn't be knuckling
Perfect	V-ing perfect
I mustn't have knuckled you mustn't have knuckled he mustn't have knuckled we mustn't have knuckled you mustn't have knuckled they mustn't have knuckled	I mustn't have been knuckling you mustn't have been knuckling he mustn't have been knuckling we mustn't have been knuckling you mustn't have been knuckling they mustn't have been knuckling

Interrogative form

Simple form	V-ing form
must I knuckle? must you knuckle? must he knuckle? must we knuckle? must you knuckle? must they knuckle?	must I be knuckling? must you be knuckling? must he be knuckling? must we be knuckling? must you be knuckling? must they be knuckling?
Perfect	V-ing perfect
must I have knuckled? must you have knuckled? must he have knuckled? must we have knuckled? must you have knuckled? must they have knuckled?	must I have been knuckling? must you have been knuckling? must he have been knuckling? must we have been knuckling? must you have been knuckling? must they have been knuckling?

Interro-negative form

Simple form	V-ing form
mustn't I knuckle? mustn't you knuckle? mustn't he knuckle? mustn't we knuckle? mustn't you knuckle? mustn't they knuckle?	mustn't I be knuckling? mustn't you be knuckling? mustn't he be knuckling? mustn't we be knuckling? mustn't you be knuckling? mustn't they be knuckling?
Perfect	V-ing perfect
mustn't I have knuckled? mustn't you have knuckled? mustn't he have knuckled? mustn't we have knuckled? mustn't you have knuckled? mustn't they have knuckled?	mustn't I have been knuckling? mustn't you have been knuckling? mustn't he have been knuckling? mustn't we have been knuckling? mustn't you have been knuckling? mustn't they have been knuckling?