must bark
Regular verb: bark - barked- barked

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must bark
you must bark
she must bark
we must bark
you must bark
they must bark 	I must be barking
you must be barking
she must be barking
we must be barking
you must be barking
they must be barking	I must have barked
you must have barked
she must have barked
we must have barked
you must have barked
they must have barked	I must have been barking
you must have been barking
she must have been barking
we must have been barking
you must have been barking
they must have been barking	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not bark
you must not bark
she must not bark
we must not bark
you must not bark
they must not bark 	I must not be barking
you must not be barking
she must not be barking
we must not be barking
you must not be barking
they must not be barking	I must not have barked
you must not have barked
she must not have barked
we must not have barked
you must not have barked
they must not have barked	I must not have been barking
you must not have been barking
she must not have been barking
we must not have been barking
you must not have been barking
they must not have been barking	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I bark?
must you bark?
must she bark?
must we bark?
must you bark?
must they bark? 	must I be barking?
must you be barking?
must she be barking?
must we be barking?
must you be barking?
must they be barking? 	must I have barked?
must you have barked?
must she have barked?
must we have barked?
must you have barked?
must they have barked? 	must I have been barking?
must you have been barking?
must she have been barking?
must we have been barking?
must you have been barking?
must they have been barking? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not bark?
must you not bark?
must she not bark?
must we not bark?
must you not bark?
must they not bark? 	must I not be barking?
must you not be barking?
must she not be barking?
must we not be barking?
must you not be barking?
must they not be barking? 	must I not have barked?
must you not have barked?
must she not have barked?
must we not have barked?
must you not have barked?
must they not have barked? 	must I not have been barking?
must you not have been barking?
must she not have been barking?
must we not have been barking?
must you not have been barking?
must they not have been barking?