English verb conjugation
MUST QUAIL

Regular verb: quail - quailed - quailed

Affirmation

Simple form	V-ing form
I must quail you must quail she must quail we must quail you must quail they must quail	I must be quailing you must be quailing she must be quailing we must be quailing you must be quailing they must be quailing
Perfect	V-ing perfect
I must have quailed you must have quailed she must have quailed we must have quailed you must have quailed they must have quailed	I must have been quailing you must have been quailing she must have been quailing we must have been quailing you must have been quailing they must have been quailing

Negation

Simple form	V-ing form
I mustn't quail you mustn't quail she mustn't quail we mustn't quail you mustn't quail they mustn't quail	I mustn't be quailing you mustn't be quailing she mustn't be quailing we mustn't be quailing you mustn't be quailing they mustn't be quailing
Perfect	V-ing perfect
I mustn't have quailed you mustn't have quailed she mustn't have quailed we mustn't have quailed you mustn't have quailed they mustn't have quailed	I mustn't have been quailing you mustn't have been quailing she mustn't have been quailing we mustn't have been quailing you mustn't have been quailing they mustn't have been quailing

Interrogative form

Simple form	V-ing form
must I quail? must you quail? must she quail? must we quail? must you quail? must they quail?	must I be quailing? must you be quailing? must she be quailing? must we be quailing? must you be quailing? must they be quailing?
Perfect	V-ing perfect
must I have quailed? must you have quailed? must she have quailed? must we have quailed? must you have quailed? must they have quailed?	must I have been quailing? must you have been quailing? must she have been quailing? must we have been quailing? must you have been quailing? must they have been quailing?

Interro-negative form

Simple form	V-ing form
mustn't I quail? mustn't you quail? mustn't she quail? mustn't we quail? mustn't you quail? mustn't they quail?	mustn't I be quailing? mustn't you be quailing? mustn't she be quailing? mustn't we be quailing? mustn't you be quailing? mustn't they be quailing?
Perfect	V-ing perfect
mustn't I have quailed? mustn't you have quailed? mustn't she have quailed? mustn't we have quailed? mustn't you have quailed? mustn't they have quailed?	mustn't I have been quailing? mustn't you have been quailing? mustn't she have been quailing? mustn't we have been quailing? mustn't you have been quailing? mustn't they have been quailing?