must prebook
Regular verb: prebook - prebooked- prebooked

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must prebook
you must prebook
he must prebook
we must prebook
you must prebook
they must prebook 	I must be prebooking
you must be prebooking
he must be prebooking
we must be prebooking
you must be prebooking
they must be prebooking	I must have prebooked
you must have prebooked
he must have prebooked
we must have prebooked
you must have prebooked
they must have prebooked	I must have been prebooking
you must have been prebooking
he must have been prebooking
we must have been prebooking
you must have been prebooking
they must have been prebooking	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not prebook
you must not prebook
he must not prebook
we must not prebook
you must not prebook
they must not prebook 	I must not be prebooking
you must not be prebooking
he must not be prebooking
we must not be prebooking
you must not be prebooking
they must not be prebooking	I must not have prebooked
you must not have prebooked
he must not have prebooked
we must not have prebooked
you must not have prebooked
they must not have prebooked	I must not have been prebooking
you must not have been prebooking
he must not have been prebooking
we must not have been prebooking
you must not have been prebooking
they must not have been prebooking	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I prebook?
must you prebook?
must he prebook?
must we prebook?
must you prebook?
must they prebook? 	must I be prebooking?
must you be prebooking?
must he be prebooking?
must we be prebooking?
must you be prebooking?
must they be prebooking? 	must I have prebooked?
must you have prebooked?
must he have prebooked?
must we have prebooked?
must you have prebooked?
must they have prebooked? 	must I have been prebooking?
must you have been prebooking?
must he have been prebooking?
must we have been prebooking?
must you have been prebooking?
must they have been prebooking? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not prebook?
must you not prebook?
must he not prebook?
must we not prebook?
must you not prebook?
must they not prebook? 	must I not be prebooking?
must you not be prebooking?
must he not be prebooking?
must we not be prebooking?
must you not be prebooking?
must they not be prebooking? 	must I not have prebooked?
must you not have prebooked?
must he not have prebooked?
must we not have prebooked?
must you not have prebooked?
must they not have prebooked? 	must I not have been prebooking?
must you not have been prebooking?
must he not have been prebooking?
must we not have been prebooking?
must you not have been prebooking?
must they not have been prebooking?