must vouchsafe
Regular verb: vouchsafe - vouchsafed- vouchsafed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must vouchsafe
you must vouchsafe
he must vouchsafe
we must vouchsafe
you must vouchsafe
they must vouchsafe 	I must be vouchsafing
you must be vouchsafing
he must be vouchsafing
we must be vouchsafing
you must be vouchsafing
they must be vouchsafing	I must have vouchsafed
you must have vouchsafed
he must have vouchsafed
we must have vouchsafed
you must have vouchsafed
they must have vouchsafed	I must have been vouchsafing
you must have been vouchsafing
he must have been vouchsafing
we must have been vouchsafing
you must have been vouchsafing
they must have been vouchsafing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't vouchsafe
you mustn't vouchsafe
he mustn't vouchsafe
we mustn't vouchsafe
you mustn't vouchsafe
they mustn't vouchsafe 	I mustn't be vouchsafing
you mustn't be vouchsafing
he mustn't be vouchsafing
we mustn't be vouchsafing
you mustn't be vouchsafing
they mustn't be vouchsafing	I mustn't have vouchsafed
you mustn't have vouchsafed
he mustn't have vouchsafed
we mustn't have vouchsafed
you mustn't have vouchsafed
they mustn't have vouchsafed	I mustn't have been vouchsafing
you mustn't have been vouchsafing
he mustn't have been vouchsafing
we mustn't have been vouchsafing
you mustn't have been vouchsafing
they mustn't have been vouchsafing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I vouchsafe?
must you vouchsafe?
must he vouchsafe?
must we vouchsafe?
must you vouchsafe?
must they vouchsafe? 	must I be vouchsafing?
must you be vouchsafing?
must he be vouchsafing?
must we be vouchsafing?
must you be vouchsafing?
must they be vouchsafing? 	must I have vouchsafed?
must you have vouchsafed?
must he have vouchsafed?
must we have vouchsafed?
must you have vouchsafed?
must they have vouchsafed? 	must I have been vouchsafing?
must you have been vouchsafing?
must he have been vouchsafing?
must we have been vouchsafing?
must you have been vouchsafing?
must they have been vouchsafing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I vouchsafe?
mustn't you vouchsafe?
mustn't he vouchsafe?
mustn't we vouchsafe?
mustn't you vouchsafe?
mustn't they vouchsafe? 	mustn't I be vouchsafing?
mustn't you be vouchsafing?
mustn't he be vouchsafing?
mustn't we be vouchsafing?
mustn't you be vouchsafing?
mustn't they be vouchsafing? 	mustn't I have vouchsafed?
mustn't you have vouchsafed?
mustn't he have vouchsafed?
mustn't we have vouchsafed?
mustn't you have vouchsafed?
mustn't they have vouchsafed? 	mustn't I have been vouchsafing?
mustn't you have been vouchsafing?
mustn't he have been vouchsafing?
mustn't we have been vouchsafing?
mustn't you have been vouchsafing?
mustn't they have been vouchsafing?