English verb conjugation
MUST THREATEN

Regular verb: threaten - threatened - threatened

Affirmation

Simple form	V-ing form
I must threaten you must threaten she must threaten we must threaten you must threaten they must threaten	I must be threatening you must be threatening she must be threatening we must be threatening you must be threatening they must be threatening
Perfect	V-ing perfect
I must have threatened you must have threatened she must have threatened we must have threatened you must have threatened they must have threatened	I must have been threatening you must have been threatening she must have been threatening we must have been threatening you must have been threatening they must have been threatening

Negation

Simple form	V-ing form
I mustn't threaten you mustn't threaten she mustn't threaten we mustn't threaten you mustn't threaten they mustn't threaten	I mustn't be threatening you mustn't be threatening she mustn't be threatening we mustn't be threatening you mustn't be threatening they mustn't be threatening
Perfect	V-ing perfect
I mustn't have threatened you mustn't have threatened she mustn't have threatened we mustn't have threatened you mustn't have threatened they mustn't have threatened	I mustn't have been threatening you mustn't have been threatening she mustn't have been threatening we mustn't have been threatening you mustn't have been threatening they mustn't have been threatening

Interrogative form

Simple form	V-ing form
must I threaten? must you threaten? must she threaten? must we threaten? must you threaten? must they threaten?	must I be threatening? must you be threatening? must she be threatening? must we be threatening? must you be threatening? must they be threatening?
Perfect	V-ing perfect
must I have threatened? must you have threatened? must she have threatened? must we have threatened? must you have threatened? must they have threatened?	must I have been threatening? must you have been threatening? must she have been threatening? must we have been threatening? must you have been threatening? must they have been threatening?

Interro-negative form

Simple form	V-ing form
mustn't I threaten? mustn't you threaten? mustn't she threaten? mustn't we threaten? mustn't you threaten? mustn't they threaten?	mustn't I be threatening? mustn't you be threatening? mustn't she be threatening? mustn't we be threatening? mustn't you be threatening? mustn't they be threatening?
Perfect	V-ing perfect
mustn't I have threatened? mustn't you have threatened? mustn't she have threatened? mustn't we have threatened? mustn't you have threatened? mustn't they have threatened?	mustn't I have been threatening? mustn't you have been threatening? mustn't she have been threatening? mustn't we have been threatening? mustn't you have been threatening? mustn't they have been threatening?