must attach
Regular verb: attach - attached- attached

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must attach
you must attach
he must attach
we must attach
you must attach
they must attach 	I must be attaching
you must be attaching
he must be attaching
we must be attaching
you must be attaching
they must be attaching	I must have attached
you must have attached
he must have attached
we must have attached
you must have attached
they must have attached	I must have been attaching
you must have been attaching
he must have been attaching
we must have been attaching
you must have been attaching
they must have been attaching	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't attach
you mustn't attach
he mustn't attach
we mustn't attach
you mustn't attach
they mustn't attach 	I mustn't be attaching
you mustn't be attaching
he mustn't be attaching
we mustn't be attaching
you mustn't be attaching
they mustn't be attaching	I mustn't have attached
you mustn't have attached
he mustn't have attached
we mustn't have attached
you mustn't have attached
they mustn't have attached	I mustn't have been attaching
you mustn't have been attaching
he mustn't have been attaching
we mustn't have been attaching
you mustn't have been attaching
they mustn't have been attaching	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I attach?
must you attach?
must he attach?
must we attach?
must you attach?
must they attach? 	must I be attaching?
must you be attaching?
must he be attaching?
must we be attaching?
must you be attaching?
must they be attaching? 	must I have attached?
must you have attached?
must he have attached?
must we have attached?
must you have attached?
must they have attached? 	must I have been attaching?
must you have been attaching?
must he have been attaching?
must we have been attaching?
must you have been attaching?
must they have been attaching? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I attach?
mustn't you attach?
mustn't he attach?
mustn't we attach?
mustn't you attach?
mustn't they attach? 	mustn't I be attaching?
mustn't you be attaching?
mustn't he be attaching?
mustn't we be attaching?
mustn't you be attaching?
mustn't they be attaching? 	mustn't I have attached?
mustn't you have attached?
mustn't he have attached?
mustn't we have attached?
mustn't you have attached?
mustn't they have attached? 	mustn't I have been attaching?
mustn't you have been attaching?
mustn't he have been attaching?
mustn't we have been attaching?
mustn't you have been attaching?
mustn't they have been attaching?