English verb conjugation
MUST PREBOARD

Regular verb: preboard - preboarded - preboarded

Affirmation

Simple form	V-ing form
I must preboard you must preboard he must preboard we must preboard you must preboard they must preboard	I must be preboarding you must be preboarding he must be preboarding we must be preboarding you must be preboarding they must be preboarding
Perfect	V-ing perfect
I must have preboarded you must have preboarded he must have preboarded we must have preboarded you must have preboarded they must have preboarded	I must have been preboarding you must have been preboarding he must have been preboarding we must have been preboarding you must have been preboarding they must have been preboarding

Negation

Simple form	V-ing form
I must not preboard you must not preboard he must not preboard we must not preboard you must not preboard they must not preboard	I must not be preboarding you must not be preboarding he must not be preboarding we must not be preboarding you must not be preboarding they must not be preboarding
Perfect	V-ing perfect
I must not have preboarded you must not have preboarded he must not have preboarded we must not have preboarded you must not have preboarded they must not have preboarded	I must not have been preboarding you must not have been preboarding he must not have been preboarding we must not have been preboarding you must not have been preboarding they must not have been preboarding

Interrogative form

Simple form	V-ing form
must I preboard? must you preboard? must he preboard? must we preboard? must you preboard? must they preboard?	must I be preboarding? must you be preboarding? must he be preboarding? must we be preboarding? must you be preboarding? must they be preboarding?
Perfect	V-ing perfect
must I have preboarded? must you have preboarded? must he have preboarded? must we have preboarded? must you have preboarded? must they have preboarded?	must I have been preboarding? must you have been preboarding? must he have been preboarding? must we have been preboarding? must you have been preboarding? must they have been preboarding?

Interro-negative form

Simple form	V-ing form
must I not preboard? must you not preboard? must he not preboard? must we not preboard? must you not preboard? must they not preboard?	must I not be preboarding? must you not be preboarding? must he not be preboarding? must we not be preboarding? must you not be preboarding? must they not be preboarding?
Perfect	V-ing perfect
must I not have preboarded? must you not have preboarded? must he not have preboarded? must we not have preboarded? must you not have preboarded? must they not have preboarded?	must I not have been preboarding? must you not have been preboarding? must he not have been preboarding? must we not have been preboarding? must you not have been preboarding? must they not have been preboarding?