must fax
Regular verb: fax - faxed- faxed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must fax
you must fax
she must fax
we must fax
you must fax
they must fax 	I must be faxing
you must be faxing
she must be faxing
we must be faxing
you must be faxing
they must be faxing	I must have faxed
you must have faxed
she must have faxed
we must have faxed
you must have faxed
they must have faxed	I must have been faxing
you must have been faxing
she must have been faxing
we must have been faxing
you must have been faxing
they must have been faxing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not fax
you must not fax
she must not fax
we must not fax
you must not fax
they must not fax 	I must not be faxing
you must not be faxing
she must not be faxing
we must not be faxing
you must not be faxing
they must not be faxing	I must not have faxed
you must not have faxed
she must not have faxed
we must not have faxed
you must not have faxed
they must not have faxed	I must not have been faxing
you must not have been faxing
she must not have been faxing
we must not have been faxing
you must not have been faxing
they must not have been faxing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I fax?
must you fax?
must she fax?
must we fax?
must you fax?
must they fax? 	must I be faxing?
must you be faxing?
must she be faxing?
must we be faxing?
must you be faxing?
must they be faxing? 	must I have faxed?
must you have faxed?
must she have faxed?
must we have faxed?
must you have faxed?
must they have faxed? 	must I have been faxing?
must you have been faxing?
must she have been faxing?
must we have been faxing?
must you have been faxing?
must they have been faxing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not fax?
must you not fax?
must she not fax?
must we not fax?
must you not fax?
must they not fax? 	must I not be faxing?
must you not be faxing?
must she not be faxing?
must we not be faxing?
must you not be faxing?
must they not be faxing? 	must I not have faxed?
must you not have faxed?
must she not have faxed?
must we not have faxed?
must you not have faxed?
must they not have faxed? 	must I not have been faxing?
must you not have been faxing?
must she not have been faxing?
must we not have been faxing?
must you not have been faxing?
must they not have been faxing?