must sheaf
Regular verb: sheaf - sheafed- sheafed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must sheaf
you must sheaf
she must sheaf
we must sheaf
you must sheaf
they must sheaf 	I must be sheafing
you must be sheafing
she must be sheafing
we must be sheafing
you must be sheafing
they must be sheafing	I must have sheafed
you must have sheafed
she must have sheafed
we must have sheafed
you must have sheafed
they must have sheafed	I must have been sheafing
you must have been sheafing
she must have been sheafing
we must have been sheafing
you must have been sheafing
they must have been sheafing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not sheaf
you must not sheaf
she must not sheaf
we must not sheaf
you must not sheaf
they must not sheaf 	I must not be sheafing
you must not be sheafing
she must not be sheafing
we must not be sheafing
you must not be sheafing
they must not be sheafing	I must not have sheafed
you must not have sheafed
she must not have sheafed
we must not have sheafed
you must not have sheafed
they must not have sheafed	I must not have been sheafing
you must not have been sheafing
she must not have been sheafing
we must not have been sheafing
you must not have been sheafing
they must not have been sheafing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I sheaf?
must you sheaf?
must she sheaf?
must we sheaf?
must you sheaf?
must they sheaf? 	must I be sheafing?
must you be sheafing?
must she be sheafing?
must we be sheafing?
must you be sheafing?
must they be sheafing? 	must I have sheafed?
must you have sheafed?
must she have sheafed?
must we have sheafed?
must you have sheafed?
must they have sheafed? 	must I have been sheafing?
must you have been sheafing?
must she have been sheafing?
must we have been sheafing?
must you have been sheafing?
must they have been sheafing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not sheaf?
must you not sheaf?
must she not sheaf?
must we not sheaf?
must you not sheaf?
must they not sheaf? 	must I not be sheafing?
must you not be sheafing?
must she not be sheafing?
must we not be sheafing?
must you not be sheafing?
must they not be sheafing? 	must I not have sheafed?
must you not have sheafed?
must she not have sheafed?
must we not have sheafed?
must you not have sheafed?
must they not have sheafed? 	must I not have been sheafing?
must you not have been sheafing?
must she not have been sheafing?
must we not have been sheafing?
must you not have been sheafing?
must they not have been sheafing?