must luff
Regular verb: luff - luffed- luffed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must luff
you must luff
she must luff
we must luff
you must luff
they must luff 	I must be luffing
you must be luffing
she must be luffing
we must be luffing
you must be luffing
they must be luffing	I must have luffed
you must have luffed
she must have luffed
we must have luffed
you must have luffed
they must have luffed	I must have been luffing
you must have been luffing
she must have been luffing
we must have been luffing
you must have been luffing
they must have been luffing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't luff
you mustn't luff
she mustn't luff
we mustn't luff
you mustn't luff
they mustn't luff 	I mustn't be luffing
you mustn't be luffing
she mustn't be luffing
we mustn't be luffing
you mustn't be luffing
they mustn't be luffing	I mustn't have luffed
you mustn't have luffed
she mustn't have luffed
we mustn't have luffed
you mustn't have luffed
they mustn't have luffed	I mustn't have been luffing
you mustn't have been luffing
she mustn't have been luffing
we mustn't have been luffing
you mustn't have been luffing
they mustn't have been luffing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I luff?
must you luff?
must she luff?
must we luff?
must you luff?
must they luff? 	must I be luffing?
must you be luffing?
must she be luffing?
must we be luffing?
must you be luffing?
must they be luffing? 	must I have luffed?
must you have luffed?
must she have luffed?
must we have luffed?
must you have luffed?
must they have luffed? 	must I have been luffing?
must you have been luffing?
must she have been luffing?
must we have been luffing?
must you have been luffing?
must they have been luffing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I luff?
mustn't you luff?
mustn't she luff?
mustn't we luff?
mustn't you luff?
mustn't they luff? 	mustn't I be luffing?
mustn't you be luffing?
mustn't she be luffing?
mustn't we be luffing?
mustn't you be luffing?
mustn't they be luffing? 	mustn't I have luffed?
mustn't you have luffed?
mustn't she have luffed?
mustn't we have luffed?
mustn't you have luffed?
mustn't they have luffed? 	mustn't I have been luffing?
mustn't you have been luffing?
mustn't she have been luffing?
mustn't we have been luffing?
mustn't you have been luffing?
mustn't they have been luffing?