must lichen
Regular verb: lichen - lichened- lichened

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must lichen
you must lichen
he must lichen
we must lichen
you must lichen
they must lichen 	I must be lichening
you must be lichening
he must be lichening
we must be lichening
you must be lichening
they must be lichening	I must have lichened
you must have lichened
he must have lichened
we must have lichened
you must have lichened
they must have lichened	I must have been lichening
you must have been lichening
he must have been lichening
we must have been lichening
you must have been lichening
they must have been lichening	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't lichen
you mustn't lichen
he mustn't lichen
we mustn't lichen
you mustn't lichen
they mustn't lichen 	I mustn't be lichening
you mustn't be lichening
he mustn't be lichening
we mustn't be lichening
you mustn't be lichening
they mustn't be lichening	I mustn't have lichened
you mustn't have lichened
he mustn't have lichened
we mustn't have lichened
you mustn't have lichened
they mustn't have lichened	I mustn't have been lichening
you mustn't have been lichening
he mustn't have been lichening
we mustn't have been lichening
you mustn't have been lichening
they mustn't have been lichening	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I lichen?
must you lichen?
must he lichen?
must we lichen?
must you lichen?
must they lichen? 	must I be lichening?
must you be lichening?
must he be lichening?
must we be lichening?
must you be lichening?
must they be lichening? 	must I have lichened?
must you have lichened?
must he have lichened?
must we have lichened?
must you have lichened?
must they have lichened? 	must I have been lichening?
must you have been lichening?
must he have been lichening?
must we have been lichening?
must you have been lichening?
must they have been lichening? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I lichen?
mustn't you lichen?
mustn't he lichen?
mustn't we lichen?
mustn't you lichen?
mustn't they lichen? 	mustn't I be lichening?
mustn't you be lichening?
mustn't he be lichening?
mustn't we be lichening?
mustn't you be lichening?
mustn't they be lichening? 	mustn't I have lichened?
mustn't you have lichened?
mustn't he have lichened?
mustn't we have lichened?
mustn't you have lichened?
mustn't they have lichened? 	mustn't I have been lichening?
mustn't you have been lichening?
mustn't he have been lichening?
mustn't we have been lichening?
mustn't you have been lichening?
mustn't they have been lichening?