English verb conjugation
MUST FUR

Regular verb: fur - furred - furred

Affirmation

Simple form	V-ing form
I must fur you must fur he must fur we must fur you must fur they must fur	I must be furring you must be furring he must be furring we must be furring you must be furring they must be furring
Perfect	V-ing perfect
I must have furred you must have furred he must have furred we must have furred you must have furred they must have furred	I must have been furring you must have been furring he must have been furring we must have been furring you must have been furring they must have been furring

Negation

Simple form	V-ing form
I mustn't fur you mustn't fur he mustn't fur we mustn't fur you mustn't fur they mustn't fur	I mustn't be furring you mustn't be furring he mustn't be furring we mustn't be furring you mustn't be furring they mustn't be furring
Perfect	V-ing perfect
I mustn't have furred you mustn't have furred he mustn't have furred we mustn't have furred you mustn't have furred they mustn't have furred	I mustn't have been furring you mustn't have been furring he mustn't have been furring we mustn't have been furring you mustn't have been furring they mustn't have been furring

Interrogative form

Simple form	V-ing form
must I fur? must you fur? must he fur? must we fur? must you fur? must they fur?	must I be furring? must you be furring? must he be furring? must we be furring? must you be furring? must they be furring?
Perfect	V-ing perfect
must I have furred? must you have furred? must he have furred? must we have furred? must you have furred? must they have furred?	must I have been furring? must you have been furring? must he have been furring? must we have been furring? must you have been furring? must they have been furring?

Interro-negative form

Simple form	V-ing form
mustn't I fur? mustn't you fur? mustn't he fur? mustn't we fur? mustn't you fur? mustn't they fur?	mustn't I be furring? mustn't you be furring? mustn't he be furring? mustn't we be furring? mustn't you be furring? mustn't they be furring?
Perfect	V-ing perfect
mustn't I have furred? mustn't you have furred? mustn't he have furred? mustn't we have furred? mustn't you have furred? mustn't they have furred?	mustn't I have been furring? mustn't you have been furring? mustn't he have been furring? mustn't we have been furring? mustn't you have been furring? mustn't they have been furring?