must crease
Regular verb: crease - creased- creased

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must crease
you must crease
he must crease
we must crease
you must crease
they must crease 	I must be creasing
you must be creasing
he must be creasing
we must be creasing
you must be creasing
they must be creasing	I must have creased
you must have creased
he must have creased
we must have creased
you must have creased
they must have creased	I must have been creasing
you must have been creasing
he must have been creasing
we must have been creasing
you must have been creasing
they must have been creasing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not crease
you must not crease
he must not crease
we must not crease
you must not crease
they must not crease 	I must not be creasing
you must not be creasing
he must not be creasing
we must not be creasing
you must not be creasing
they must not be creasing	I must not have creased
you must not have creased
he must not have creased
we must not have creased
you must not have creased
they must not have creased	I must not have been creasing
you must not have been creasing
he must not have been creasing
we must not have been creasing
you must not have been creasing
they must not have been creasing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I crease?
must you crease?
must he crease?
must we crease?
must you crease?
must they crease? 	must I be creasing?
must you be creasing?
must he be creasing?
must we be creasing?
must you be creasing?
must they be creasing? 	must I have creased?
must you have creased?
must he have creased?
must we have creased?
must you have creased?
must they have creased? 	must I have been creasing?
must you have been creasing?
must he have been creasing?
must we have been creasing?
must you have been creasing?
must they have been creasing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not crease?
must you not crease?
must he not crease?
must we not crease?
must you not crease?
must they not crease? 	must I not be creasing?
must you not be creasing?
must he not be creasing?
must we not be creasing?
must you not be creasing?
must they not be creasing? 	must I not have creased?
must you not have creased?
must he not have creased?
must we not have creased?
must you not have creased?
must they not have creased? 	must I not have been creasing?
must you not have been creasing?
must he not have been creasing?
must we not have been creasing?
must you not have been creasing?
must they not have been creasing?