must couple
Regular verb: couple - coupled- coupled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must couple
you must couple
he must couple
we must couple
you must couple
they must couple 	I must be coupling
you must be coupling
he must be coupling
we must be coupling
you must be coupling
they must be coupling	I must have coupled
you must have coupled
he must have coupled
we must have coupled
you must have coupled
they must have coupled	I must have been coupling
you must have been coupling
he must have been coupling
we must have been coupling
you must have been coupling
they must have been coupling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't couple
you mustn't couple
he mustn't couple
we mustn't couple
you mustn't couple
they mustn't couple 	I mustn't be coupling
you mustn't be coupling
he mustn't be coupling
we mustn't be coupling
you mustn't be coupling
they mustn't be coupling	I mustn't have coupled
you mustn't have coupled
he mustn't have coupled
we mustn't have coupled
you mustn't have coupled
they mustn't have coupled	I mustn't have been coupling
you mustn't have been coupling
he mustn't have been coupling
we mustn't have been coupling
you mustn't have been coupling
they mustn't have been coupling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I couple?
must you couple?
must he couple?
must we couple?
must you couple?
must they couple? 	must I be coupling?
must you be coupling?
must he be coupling?
must we be coupling?
must you be coupling?
must they be coupling? 	must I have coupled?
must you have coupled?
must he have coupled?
must we have coupled?
must you have coupled?
must they have coupled? 	must I have been coupling?
must you have been coupling?
must he have been coupling?
must we have been coupling?
must you have been coupling?
must they have been coupling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I couple?
mustn't you couple?
mustn't he couple?
mustn't we couple?
mustn't you couple?
mustn't they couple? 	mustn't I be coupling?
mustn't you be coupling?
mustn't he be coupling?
mustn't we be coupling?
mustn't you be coupling?
mustn't they be coupling? 	mustn't I have coupled?
mustn't you have coupled?
mustn't he have coupled?
mustn't we have coupled?
mustn't you have coupled?
mustn't they have coupled? 	mustn't I have been coupling?
mustn't you have been coupling?
mustn't he have been coupling?
mustn't we have been coupling?
mustn't you have been coupling?
mustn't they have been coupling?