English verb conjugation
MUST CHALLENGE

Regular verb: challenge - challenged - challenged

Affirmation

Simple form	V-ing form
I must challenge you must challenge he must challenge we must challenge you must challenge they must challenge	I must be challenging you must be challenging he must be challenging we must be challenging you must be challenging they must be challenging
Perfect	V-ing perfect
I must have challenged you must have challenged he must have challenged we must have challenged you must have challenged they must have challenged	I must have been challenging you must have been challenging he must have been challenging we must have been challenging you must have been challenging they must have been challenging

Negation

Simple form	V-ing form
I mustn't challenge you mustn't challenge he mustn't challenge we mustn't challenge you mustn't challenge they mustn't challenge	I mustn't be challenging you mustn't be challenging he mustn't be challenging we mustn't be challenging you mustn't be challenging they mustn't be challenging
Perfect	V-ing perfect
I mustn't have challenged you mustn't have challenged he mustn't have challenged we mustn't have challenged you mustn't have challenged they mustn't have challenged	I mustn't have been challenging you mustn't have been challenging he mustn't have been challenging we mustn't have been challenging you mustn't have been challenging they mustn't have been challenging

Interrogative form

Simple form	V-ing form
must I challenge? must you challenge? must he challenge? must we challenge? must you challenge? must they challenge?	must I be challenging? must you be challenging? must he be challenging? must we be challenging? must you be challenging? must they be challenging?
Perfect	V-ing perfect
must I have challenged? must you have challenged? must he have challenged? must we have challenged? must you have challenged? must they have challenged?	must I have been challenging? must you have been challenging? must he have been challenging? must we have been challenging? must you have been challenging? must they have been challenging?

Interro-negative form

Simple form	V-ing form
mustn't I challenge? mustn't you challenge? mustn't he challenge? mustn't we challenge? mustn't you challenge? mustn't they challenge?	mustn't I be challenging? mustn't you be challenging? mustn't he be challenging? mustn't we be challenging? mustn't you be challenging? mustn't they be challenging?
Perfect	V-ing perfect
mustn't I have challenged? mustn't you have challenged? mustn't he have challenged? mustn't we have challenged? mustn't you have challenged? mustn't they have challenged?	mustn't I have been challenging? mustn't you have been challenging? mustn't he have been challenging? mustn't we have been challenging? mustn't you have been challenging? mustn't they have been challenging?