must crossruff
Regular verb: crossruff - crossruffed- crossruffed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must crossruff
you must crossruff
he must crossruff
we must crossruff
you must crossruff
they must crossruff 	I must be crossruffing
you must be crossruffing
he must be crossruffing
we must be crossruffing
you must be crossruffing
they must be crossruffing	I must have crossruffed
you must have crossruffed
he must have crossruffed
we must have crossruffed
you must have crossruffed
they must have crossruffed	I must have been crossruffing
you must have been crossruffing
he must have been crossruffing
we must have been crossruffing
you must have been crossruffing
they must have been crossruffing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't crossruff
you mustn't crossruff
he mustn't crossruff
we mustn't crossruff
you mustn't crossruff
they mustn't crossruff 	I mustn't be crossruffing
you mustn't be crossruffing
he mustn't be crossruffing
we mustn't be crossruffing
you mustn't be crossruffing
they mustn't be crossruffing	I mustn't have crossruffed
you mustn't have crossruffed
he mustn't have crossruffed
we mustn't have crossruffed
you mustn't have crossruffed
they mustn't have crossruffed	I mustn't have been crossruffing
you mustn't have been crossruffing
he mustn't have been crossruffing
we mustn't have been crossruffing
you mustn't have been crossruffing
they mustn't have been crossruffing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I crossruff?
must you crossruff?
must he crossruff?
must we crossruff?
must you crossruff?
must they crossruff? 	must I be crossruffing?
must you be crossruffing?
must he be crossruffing?
must we be crossruffing?
must you be crossruffing?
must they be crossruffing? 	must I have crossruffed?
must you have crossruffed?
must he have crossruffed?
must we have crossruffed?
must you have crossruffed?
must they have crossruffed? 	must I have been crossruffing?
must you have been crossruffing?
must he have been crossruffing?
must we have been crossruffing?
must you have been crossruffing?
must they have been crossruffing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I crossruff?
mustn't you crossruff?
mustn't he crossruff?
mustn't we crossruff?
mustn't you crossruff?
mustn't they crossruff? 	mustn't I be crossruffing?
mustn't you be crossruffing?
mustn't he be crossruffing?
mustn't we be crossruffing?
mustn't you be crossruffing?
mustn't they be crossruffing? 	mustn't I have crossruffed?
mustn't you have crossruffed?
mustn't he have crossruffed?
mustn't we have crossruffed?
mustn't you have crossruffed?
mustn't they have crossruffed? 	mustn't I have been crossruffing?
mustn't you have been crossruffing?
mustn't he have been crossruffing?
mustn't we have been crossruffing?
mustn't you have been crossruffing?
mustn't they have been crossruffing?