English verb conjugation
MUST UNDERGIRD

Irregular verb: undergird - undergirt, undergirded - undergirt, undergirded

Affirmation

Simple form	V-ing form
I must undergird you must undergird he must undergird we must undergird you must undergird they must undergird	I must be undergirding you must be undergirding he must be undergirding we must be undergirding you must be undergirding they must be undergirding
Perfect	V-ing perfect
I must have undergirt, undergirded you must have undergirt, undergirded he must have undergirt, undergirded we must have undergirt, undergirded you must have undergirt, undergirded they must have undergirt, undergirded	I must have been undergirding you must have been undergirding he must have been undergirding we must have been undergirding you must have been undergirding they must have been undergirding

Negation

Simple form	V-ing form
I must not undergird you must not undergird he must not undergird we must not undergird you must not undergird they must not undergird	I must not be undergirding you must not be undergirding he must not be undergirding we must not be undergirding you must not be undergirding they must not be undergirding
Perfect	V-ing perfect
I must not have undergirt, undergirded you must not have undergirt, undergirded he must not have undergirt, undergirded we must not have undergirt, undergirded you must not have undergirt, undergirded they must not have undergirt, undergirded	I must not have been undergirding you must not have been undergirding he must not have been undergirding we must not have been undergirding you must not have been undergirding they must not have been undergirding

Interrogative form

Simple form	V-ing form
must I undergird? must you undergird? must he undergird? must we undergird? must you undergird? must they undergird?	must I be undergirding? must you be undergirding? must he be undergirding? must we be undergirding? must you be undergirding? must they be undergirding?
Perfect	V-ing perfect
must I have undergirt, undergirded? must you have undergirt, undergirded? must he have undergirt, undergirded? must we have undergirt, undergirded? must you have undergirt, undergirded? must they have undergirt, undergirded?	must I have been undergirding? must you have been undergirding? must he have been undergirding? must we have been undergirding? must you have been undergirding? must they have been undergirding?

Interro-negative form

Simple form	V-ing form
must I not undergird? must you not undergird? must he not undergird? must we not undergird? must you not undergird? must they not undergird?	must I not be undergirding? must you not be undergirding? must he not be undergirding? must we not be undergirding? must you not be undergirding? must they not be undergirding?
Perfect	V-ing perfect
must I not have undergirt, undergirded? must you not have undergirt, undergirded? must he not have undergirt, undergirded? must we not have undergirt, undergirded? must you not have undergirt, undergirded? must they not have undergirt, undergirded?	must I not have been undergirding? must you not have been undergirding? must he not have been undergirding? must we not have been undergirding? must you not have been undergirding? must they not have been undergirding?