English verb conjugation
MUST QUAFF

Regular verb: quaff - quaffed - quaffed

Affirmation

Simple form	V-ing form
I must quaff you must quaff she must quaff we must quaff you must quaff they must quaff	I must be quaffing you must be quaffing she must be quaffing we must be quaffing you must be quaffing they must be quaffing
Perfect	V-ing perfect
I must have quaffed you must have quaffed she must have quaffed we must have quaffed you must have quaffed they must have quaffed	I must have been quaffing you must have been quaffing she must have been quaffing we must have been quaffing you must have been quaffing they must have been quaffing

Negation

Simple form	V-ing form
I mustn't quaff you mustn't quaff she mustn't quaff we mustn't quaff you mustn't quaff they mustn't quaff	I mustn't be quaffing you mustn't be quaffing she mustn't be quaffing we mustn't be quaffing you mustn't be quaffing they mustn't be quaffing
Perfect	V-ing perfect
I mustn't have quaffed you mustn't have quaffed she mustn't have quaffed we mustn't have quaffed you mustn't have quaffed they mustn't have quaffed	I mustn't have been quaffing you mustn't have been quaffing she mustn't have been quaffing we mustn't have been quaffing you mustn't have been quaffing they mustn't have been quaffing

Interrogative form

Simple form	V-ing form
must I quaff? must you quaff? must she quaff? must we quaff? must you quaff? must they quaff?	must I be quaffing? must you be quaffing? must she be quaffing? must we be quaffing? must you be quaffing? must they be quaffing?
Perfect	V-ing perfect
must I have quaffed? must you have quaffed? must she have quaffed? must we have quaffed? must you have quaffed? must they have quaffed?	must I have been quaffing? must you have been quaffing? must she have been quaffing? must we have been quaffing? must you have been quaffing? must they have been quaffing?

Interro-negative form

Simple form	V-ing form
mustn't I quaff? mustn't you quaff? mustn't she quaff? mustn't we quaff? mustn't you quaff? mustn't they quaff?	mustn't I be quaffing? mustn't you be quaffing? mustn't she be quaffing? mustn't we be quaffing? mustn't you be quaffing? mustn't they be quaffing?
Perfect	V-ing perfect
mustn't I have quaffed? mustn't you have quaffed? mustn't she have quaffed? mustn't we have quaffed? mustn't you have quaffed? mustn't they have quaffed?	mustn't I have been quaffing? mustn't you have been quaffing? mustn't she have been quaffing? mustn't we have been quaffing? mustn't you have been quaffing? mustn't they have been quaffing?