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 must not preestablish
you must not preestablish
she must not preestablish
we must not preestablish
you must not preestablish
they must not preestablish 	I must not be preestablishing
you must not be preestablishing
she must not be preestablishing
we must not be preestablishing
you must not be preestablishing
they must not be preestablishing	I must not have preestablished
you must not have preestablished
she must not have preestablished
we must not have preestablished
you must not have preestablished
they must not have preestablished	I must not have been preestablishing
you must not have been preestablishing
she must not have been preestablishing
we must not have been preestablishing
you must not have been preestablishing
they must not 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 	
must I not preestablish?
must you not preestablish?
must she not preestablish?
must we not preestablish?
must you not preestablish?
must they not preestablish? 	must I not be preestablishing?
must you not be preestablishing?
must she not be preestablishing?
must we not be preestablishing?
must you not be preestablishing?
must they not be preestablishing? 	must I not have preestablished?
must you not have preestablished?
must she not have preestablished?
must we not have preestablished?
must you not have preestablished?
must they not have preestablished? 	must I not have been preestablishing?
must you not have been preestablishing?
must she not have been preestablishing?
must we not have been preestablishing?
must you not have been preestablishing?
must they not have been preestablishing?