must yearn
Regular verb: yearn - yearned- yearned

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must yearn
you must yearn
he must yearn
we must yearn
you must yearn
they must yearn 	I must be yearning
you must be yearning
he must be yearning
we must be yearning
you must be yearning
they must be yearning	I must have yearned
you must have yearned
he must have yearned
we must have yearned
you must have yearned
they must have yearned	I must have been yearning
you must have been yearning
he must have been yearning
we must have been yearning
you must have been yearning
they must have been yearning	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't yearn
you mustn't yearn
he mustn't yearn
we mustn't yearn
you mustn't yearn
they mustn't yearn 	I mustn't be yearning
you mustn't be yearning
he mustn't be yearning
we mustn't be yearning
you mustn't be yearning
they mustn't be yearning	I mustn't have yearned
you mustn't have yearned
he mustn't have yearned
we mustn't have yearned
you mustn't have yearned
they mustn't have yearned	I mustn't have been yearning
you mustn't have been yearning
he mustn't have been yearning
we mustn't have been yearning
you mustn't have been yearning
they mustn't have been yearning	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I yearn?
must you yearn?
must he yearn?
must we yearn?
must you yearn?
must they yearn? 	must I be yearning?
must you be yearning?
must he be yearning?
must we be yearning?
must you be yearning?
must they be yearning? 	must I have yearned?
must you have yearned?
must he have yearned?
must we have yearned?
must you have yearned?
must they have yearned? 	must I have been yearning?
must you have been yearning?
must he have been yearning?
must we have been yearning?
must you have been yearning?
must they have been yearning? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I yearn?
mustn't you yearn?
mustn't he yearn?
mustn't we yearn?
mustn't you yearn?
mustn't they yearn? 	mustn't I be yearning?
mustn't you be yearning?
mustn't he be yearning?
mustn't we be yearning?
mustn't you be yearning?
mustn't they be yearning? 	mustn't I have yearned?
mustn't you have yearned?
mustn't he have yearned?
mustn't we have yearned?
mustn't you have yearned?
mustn't they have yearned? 	mustn't I have been yearning?
mustn't you have been yearning?
mustn't he have been yearning?
mustn't we have been yearning?
mustn't you have been yearning?
mustn't they have been yearning?