must hammer
Regular verb: hammer - hammered- hammered

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must hammer
you must hammer
he must hammer
we must hammer
you must hammer
they must hammer 	I must be hammering
you must be hammering
he must be hammering
we must be hammering
you must be hammering
they must be hammering	I must have hammered
you must have hammered
he must have hammered
we must have hammered
you must have hammered
they must have hammered	I must have been hammering
you must have been hammering
he must have been hammering
we must have been hammering
you must have been hammering
they must have been hammering	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't hammer
you mustn't hammer
he mustn't hammer
we mustn't hammer
you mustn't hammer
they mustn't hammer 	I mustn't be hammering
you mustn't be hammering
he mustn't be hammering
we mustn't be hammering
you mustn't be hammering
they mustn't be hammering	I mustn't have hammered
you mustn't have hammered
he mustn't have hammered
we mustn't have hammered
you mustn't have hammered
they mustn't have hammered	I mustn't have been hammering
you mustn't have been hammering
he mustn't have been hammering
we mustn't have been hammering
you mustn't have been hammering
they mustn't have been hammering	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I hammer?
must you hammer?
must he hammer?
must we hammer?
must you hammer?
must they hammer? 	must I be hammering?
must you be hammering?
must he be hammering?
must we be hammering?
must you be hammering?
must they be hammering? 	must I have hammered?
must you have hammered?
must he have hammered?
must we have hammered?
must you have hammered?
must they have hammered? 	must I have been hammering?
must you have been hammering?
must he have been hammering?
must we have been hammering?
must you have been hammering?
must they have been hammering? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I hammer?
mustn't you hammer?
mustn't he hammer?
mustn't we hammer?
mustn't you hammer?
mustn't they hammer? 	mustn't I be hammering?
mustn't you be hammering?
mustn't he be hammering?
mustn't we be hammering?
mustn't you be hammering?
mustn't they be hammering? 	mustn't I have hammered?
mustn't you have hammered?
mustn't he have hammered?
mustn't we have hammered?
mustn't you have hammered?
mustn't they have hammered? 	mustn't I have been hammering?
mustn't you have been hammering?
mustn't he have been hammering?
mustn't we have been hammering?
mustn't you have been hammering?
mustn't they have been hammering?