must counterweigh
Regular verb: counterweigh - counterweighed- counterweighed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must counterweigh
you must counterweigh
he must counterweigh
we must counterweigh
you must counterweigh
they must counterweigh 	I must be counterweighing
you must be counterweighing
he must be counterweighing
we must be counterweighing
you must be counterweighing
they must be counterweighing	I must have counterweighed
you must have counterweighed
he must have counterweighed
we must have counterweighed
you must have counterweighed
they must have counterweighed	I must have been counterweighing
you must have been counterweighing
he must have been counterweighing
we must have been counterweighing
you must have been counterweighing
they must have been counterweighing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't counterweigh
you mustn't counterweigh
he mustn't counterweigh
we mustn't counterweigh
you mustn't counterweigh
they mustn't counterweigh 	I mustn't be counterweighing
you mustn't be counterweighing
he mustn't be counterweighing
we mustn't be counterweighing
you mustn't be counterweighing
they mustn't be counterweighing	I mustn't have counterweighed
you mustn't have counterweighed
he mustn't have counterweighed
we mustn't have counterweighed
you mustn't have counterweighed
they mustn't have counterweighed	I mustn't have been counterweighing
you mustn't have been counterweighing
he mustn't have been counterweighing
we mustn't have been counterweighing
you mustn't have been counterweighing
they mustn't have been counterweighing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I counterweigh?
must you counterweigh?
must he counterweigh?
must we counterweigh?
must you counterweigh?
must they counterweigh? 	must I be counterweighing?
must you be counterweighing?
must he be counterweighing?
must we be counterweighing?
must you be counterweighing?
must they be counterweighing? 	must I have counterweighed?
must you have counterweighed?
must he have counterweighed?
must we have counterweighed?
must you have counterweighed?
must they have counterweighed? 	must I have been counterweighing?
must you have been counterweighing?
must he have been counterweighing?
must we have been counterweighing?
must you have been counterweighing?
must they have been counterweighing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I counterweigh?
mustn't you counterweigh?
mustn't he counterweigh?
mustn't we counterweigh?
mustn't you counterweigh?
mustn't they counterweigh? 	mustn't I be counterweighing?
mustn't you be counterweighing?
mustn't he be counterweighing?
mustn't we be counterweighing?
mustn't you be counterweighing?
mustn't they be counterweighing? 	mustn't I have counterweighed?
mustn't you have counterweighed?
mustn't he have counterweighed?
mustn't we have counterweighed?
mustn't you have counterweighed?
mustn't they have counterweighed? 	mustn't I have been counterweighing?
mustn't you have been counterweighing?
mustn't he have been counterweighing?
mustn't we have been counterweighing?
mustn't you have been counterweighing?
mustn't they have been counterweighing?