must preestablish
Regular verb: preestablish - preestablished- preestablished

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must preestablish
you must preestablish
she must preestablish
we must preestablish
you must preestablish
they must preestablish 	I must be preestablishing
you must be preestablishing
she must be preestablishing
we must be preestablishing
you must be preestablishing
they must be preestablishing	I must have preestablished
you must have preestablished
she must have preestablished
we must have preestablished
you must have preestablished
they must have preestablished	I must have been preestablishing
you must have been preestablishing
she must have been preestablishing
we must have been preestablishing
you must have been preestablishing
they must have been preestablishing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't preestablish
you mustn't preestablish
she mustn't preestablish
we mustn't preestablish
you mustn't preestablish
they mustn't preestablish 	I mustn't be preestablishing
you mustn't be preestablishing
she mustn't be preestablishing
we mustn't be preestablishing
you mustn't be preestablishing
they mustn't be preestablishing	I mustn't have preestablished
you mustn't have preestablished
she mustn't have preestablished
we mustn't have preestablished
you mustn't have preestablished
they mustn't have preestablished	I mustn't have been preestablishing
you mustn't have been preestablishing
she mustn't have been preestablishing
we mustn't have been preestablishing
you mustn't have been preestablishing
they mustn't have been preestablishing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I preestablish?
must you preestablish?
must she preestablish?
must we preestablish?
must you preestablish?
must they preestablish? 	must I be preestablishing?
must you be preestablishing?
must she be preestablishing?
must we be preestablishing?
must you be preestablishing?
must they be preestablishing? 	must I have preestablished?
must you have preestablished?
must she have preestablished?
must we have preestablished?
must you have preestablished?
must they have preestablished? 	must I have been preestablishing?
must you have been preestablishing?
must she have been preestablishing?
must we have been preestablishing?
must you have been preestablishing?
must they have been preestablishing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I preestablish?
mustn't you preestablish?
mustn't she preestablish?
mustn't we preestablish?
mustn't you preestablish?
mustn't they preestablish? 	mustn't I be preestablishing?
mustn't you be preestablishing?
mustn't she be preestablishing?
mustn't we be preestablishing?
mustn't you be preestablishing?
mustn't they be preestablishing? 	mustn't I have preestablished?
mustn't you have preestablished?
mustn't she have preestablished?
mustn't we have preestablished?
mustn't you have preestablished?
mustn't they have preestablished? 	mustn't I have been preestablishing?
mustn't you have been preestablishing?
mustn't she have been preestablishing?
mustn't we have been preestablishing?
mustn't you have been preestablishing?
mustn't they have been preestablishing?