must percuss
Regular verb: percuss - percussed- percussed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must percuss
you must percuss
he must percuss
we must percuss
you must percuss
they must percuss 	I must be percussing
you must be percussing
he must be percussing
we must be percussing
you must be percussing
they must be percussing	I must have percussed
you must have percussed
he must have percussed
we must have percussed
you must have percussed
they must have percussed	I must have been percussing
you must have been percussing
he must have been percussing
we must have been percussing
you must have been percussing
they must have been percussing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not percuss
you must not percuss
he must not percuss
we must not percuss
you must not percuss
they must not percuss 	I must not be percussing
you must not be percussing
he must not be percussing
we must not be percussing
you must not be percussing
they must not be percussing	I must not have percussed
you must not have percussed
he must not have percussed
we must not have percussed
you must not have percussed
they must not have percussed	I must not have been percussing
you must not have been percussing
he must not have been percussing
we must not have been percussing
you must not have been percussing
they must not have been percussing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I percuss?
must you percuss?
must he percuss?
must we percuss?
must you percuss?
must they percuss? 	must I be percussing?
must you be percussing?
must he be percussing?
must we be percussing?
must you be percussing?
must they be percussing? 	must I have percussed?
must you have percussed?
must he have percussed?
must we have percussed?
must you have percussed?
must they have percussed? 	must I have been percussing?
must you have been percussing?
must he have been percussing?
must we have been percussing?
must you have been percussing?
must they have been percussing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not percuss?
must you not percuss?
must he not percuss?
must we not percuss?
must you not percuss?
must they not percuss? 	must I not be percussing?
must you not be percussing?
must he not be percussing?
must we not be percussing?
must you not be percussing?
must they not be percussing? 	must I not have percussed?
must you not have percussed?
must he not have percussed?
must we not have percussed?
must you not have percussed?
must they not have percussed? 	must I not have been percussing?
must you not have been percussing?
must he not have been percussing?
must we not have been percussing?
must you not have been percussing?
must they not have been percussing?