must quaver
Regular verb: quaver - quavered- quavered

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must quaver
you must quaver
she must quaver
we must quaver
you must quaver
they must quaver 	I must be quavering
you must be quavering
she must be quavering
we must be quavering
you must be quavering
they must be quavering	I must have quavered
you must have quavered
she must have quavered
we must have quavered
you must have quavered
they must have quavered	I must have been quavering
you must have been quavering
she must have been quavering
we must have been quavering
you must have been quavering
they must have been quavering	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't quaver
you mustn't quaver
she mustn't quaver
we mustn't quaver
you mustn't quaver
they mustn't quaver 	I mustn't be quavering
you mustn't be quavering
she mustn't be quavering
we mustn't be quavering
you mustn't be quavering
they mustn't be quavering	I mustn't have quavered
you mustn't have quavered
she mustn't have quavered
we mustn't have quavered
you mustn't have quavered
they mustn't have quavered	I mustn't have been quavering
you mustn't have been quavering
she mustn't have been quavering
we mustn't have been quavering
you mustn't have been quavering
they mustn't have been quavering	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I quaver?
must you quaver?
must she quaver?
must we quaver?
must you quaver?
must they quaver? 	must I be quavering?
must you be quavering?
must she be quavering?
must we be quavering?
must you be quavering?
must they be quavering? 	must I have quavered?
must you have quavered?
must she have quavered?
must we have quavered?
must you have quavered?
must they have quavered? 	must I have been quavering?
must you have been quavering?
must she have been quavering?
must we have been quavering?
must you have been quavering?
must they have been quavering? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I quaver?
mustn't you quaver?
mustn't she quaver?
mustn't we quaver?
mustn't you quaver?
mustn't they quaver? 	mustn't I be quavering?
mustn't you be quavering?
mustn't she be quavering?
mustn't we be quavering?
mustn't you be quavering?
mustn't they be quavering? 	mustn't I have quavered?
mustn't you have quavered?
mustn't she have quavered?
mustn't we have quavered?
mustn't you have quavered?
mustn't they have quavered? 	mustn't I have been quavering?
mustn't you have been quavering?
mustn't she have been quavering?
mustn't we have been quavering?
mustn't you have been quavering?
mustn't they have been quavering?