must shudder
Regular verb: shudder - shuddered- shuddered

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must shudder
you must shudder
she must shudder
we must shudder
you must shudder
they must shudder 	I must be shuddering
you must be shuddering
she must be shuddering
we must be shuddering
you must be shuddering
they must be shuddering	I must have shuddered
you must have shuddered
she must have shuddered
we must have shuddered
you must have shuddered
they must have shuddered	I must have been shuddering
you must have been shuddering
she must have been shuddering
we must have been shuddering
you must have been shuddering
they must have been shuddering	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't shudder
you mustn't shudder
she mustn't shudder
we mustn't shudder
you mustn't shudder
they mustn't shudder 	I mustn't be shuddering
you mustn't be shuddering
she mustn't be shuddering
we mustn't be shuddering
you mustn't be shuddering
they mustn't be shuddering	I mustn't have shuddered
you mustn't have shuddered
she mustn't have shuddered
we mustn't have shuddered
you mustn't have shuddered
they mustn't have shuddered	I mustn't have been shuddering
you mustn't have been shuddering
she mustn't have been shuddering
we mustn't have been shuddering
you mustn't have been shuddering
they mustn't have been shuddering	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I shudder?
must you shudder?
must she shudder?
must we shudder?
must you shudder?
must they shudder? 	must I be shuddering?
must you be shuddering?
must she be shuddering?
must we be shuddering?
must you be shuddering?
must they be shuddering? 	must I have shuddered?
must you have shuddered?
must she have shuddered?
must we have shuddered?
must you have shuddered?
must they have shuddered? 	must I have been shuddering?
must you have been shuddering?
must she have been shuddering?
must we have been shuddering?
must you have been shuddering?
must they have been shuddering? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I shudder?
mustn't you shudder?
mustn't she shudder?
mustn't we shudder?
mustn't you shudder?
mustn't they shudder? 	mustn't I be shuddering?
mustn't you be shuddering?
mustn't she be shuddering?
mustn't we be shuddering?
mustn't you be shuddering?
mustn't they be shuddering? 	mustn't I have shuddered?
mustn't you have shuddered?
mustn't she have shuddered?
mustn't we have shuddered?
mustn't you have shuddered?
mustn't they have shuddered? 	mustn't I have been shuddering?
mustn't you have been shuddering?
mustn't she have been shuddering?
mustn't we have been shuddering?
mustn't you have been shuddering?
mustn't they have been shuddering?