must participate
Regular verb: participate - participated- participated

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must participate
you must participate
she must participate
we must participate
you must participate
they must participate 	I must be participating
you must be participating
she must be participating
we must be participating
you must be participating
they must be participating	I must have participated
you must have participated
she must have participated
we must have participated
you must have participated
they must have participated	I must have been participating
you must have been participating
she must have been participating
we must have been participating
you must have been participating
they must have been participating	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't participate
you mustn't participate
she mustn't participate
we mustn't participate
you mustn't participate
they mustn't participate 	I mustn't be participating
you mustn't be participating
she mustn't be participating
we mustn't be participating
you mustn't be participating
they mustn't be participating	I mustn't have participated
you mustn't have participated
she mustn't have participated
we mustn't have participated
you mustn't have participated
they mustn't have participated	I mustn't have been participating
you mustn't have been participating
she mustn't have been participating
we mustn't have been participating
you mustn't have been participating
they mustn't have been participating	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I participate?
must you participate?
must she participate?
must we participate?
must you participate?
must they participate? 	must I be participating?
must you be participating?
must she be participating?
must we be participating?
must you be participating?
must they be participating? 	must I have participated?
must you have participated?
must she have participated?
must we have participated?
must you have participated?
must they have participated? 	must I have been participating?
must you have been participating?
must she have been participating?
must we have been participating?
must you have been participating?
must they have been participating? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I participate?
mustn't you participate?
mustn't she participate?
mustn't we participate?
mustn't you participate?
mustn't they participate? 	mustn't I be participating?
mustn't you be participating?
mustn't she be participating?
mustn't we be participating?
mustn't you be participating?
mustn't they be participating? 	mustn't I have participated?
mustn't you have participated?
mustn't she have participated?
mustn't we have participated?
mustn't you have participated?
mustn't they have participated? 	mustn't I have been participating?
mustn't you have been participating?
mustn't she have been participating?
mustn't we have been participating?
mustn't you have been participating?
mustn't they have been participating?