English verb conjugation
MUST UNTIE

Regular verb: untie - untied - untied

Affirmation

Simple form	V-ing form
I must untie you must untie he must untie we must untie you must untie they must untie	I must be untying you must be untying he must be untying we must be untying you must be untying they must be untying
Perfect	V-ing perfect
I must have untied you must have untied he must have untied we must have untied you must have untied they must have untied	I must have been untying you must have been untying he must have been untying we must have been untying you must have been untying they must have been untying

Negation

Simple form	V-ing form
I mustn't untie you mustn't untie he mustn't untie we mustn't untie you mustn't untie they mustn't untie	I mustn't be untying you mustn't be untying he mustn't be untying we mustn't be untying you mustn't be untying they mustn't be untying
Perfect	V-ing perfect
I mustn't have untied you mustn't have untied he mustn't have untied we mustn't have untied you mustn't have untied they mustn't have untied	I mustn't have been untying you mustn't have been untying he mustn't have been untying we mustn't have been untying you mustn't have been untying they mustn't have been untying

Interrogative form

Simple form	V-ing form
must I untie? must you untie? must he untie? must we untie? must you untie? must they untie?	must I be untying? must you be untying? must he be untying? must we be untying? must you be untying? must they be untying?
Perfect	V-ing perfect
must I have untied? must you have untied? must he have untied? must we have untied? must you have untied? must they have untied?	must I have been untying? must you have been untying? must he have been untying? must we have been untying? must you have been untying? must they have been untying?

Interro-negative form

Simple form	V-ing form
mustn't I untie? mustn't you untie? mustn't he untie? mustn't we untie? mustn't you untie? mustn't they untie?	mustn't I be untying? mustn't you be untying? mustn't he be untying? mustn't we be untying? mustn't you be untying? mustn't they be untying?
Perfect	V-ing perfect
mustn't I have untied? mustn't you have untied? mustn't he have untied? mustn't we have untied? mustn't you have untied? mustn't they have untied?	mustn't I have been untying? mustn't you have been untying? mustn't he have been untying? mustn't we have been untying? mustn't you have been untying? mustn't they have been untying?