must fortify
Regular verb: fortify - fortified- fortified

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must fortify
you must fortify
she must fortify
we must fortify
you must fortify
they must fortify 	I must be fortifying
you must be fortifying
she must be fortifying
we must be fortifying
you must be fortifying
they must be fortifying	I must have fortified
you must have fortified
she must have fortified
we must have fortified
you must have fortified
they must have fortified	I must have been fortifying
you must have been fortifying
she must have been fortifying
we must have been fortifying
you must have been fortifying
they must have been fortifying	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't fortify
you mustn't fortify
she mustn't fortify
we mustn't fortify
you mustn't fortify
they mustn't fortify 	I mustn't be fortifying
you mustn't be fortifying
she mustn't be fortifying
we mustn't be fortifying
you mustn't be fortifying
they mustn't be fortifying	I mustn't have fortified
you mustn't have fortified
she mustn't have fortified
we mustn't have fortified
you mustn't have fortified
they mustn't have fortified	I mustn't have been fortifying
you mustn't have been fortifying
she mustn't have been fortifying
we mustn't have been fortifying
you mustn't have been fortifying
they mustn't have been fortifying	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I fortify?
must you fortify?
must she fortify?
must we fortify?
must you fortify?
must they fortify? 	must I be fortifying?
must you be fortifying?
must she be fortifying?
must we be fortifying?
must you be fortifying?
must they be fortifying? 	must I have fortified?
must you have fortified?
must she have fortified?
must we have fortified?
must you have fortified?
must they have fortified? 	must I have been fortifying?
must you have been fortifying?
must she have been fortifying?
must we have been fortifying?
must you have been fortifying?
must they have been fortifying? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I fortify?
mustn't you fortify?
mustn't she fortify?
mustn't we fortify?
mustn't you fortify?
mustn't they fortify? 	mustn't I be fortifying?
mustn't you be fortifying?
mustn't she be fortifying?
mustn't we be fortifying?
mustn't you be fortifying?
mustn't they be fortifying? 	mustn't I have fortified?
mustn't you have fortified?
mustn't she have fortified?
mustn't we have fortified?
mustn't you have fortified?
mustn't they have fortified? 	mustn't I have been fortifying?
mustn't you have been fortifying?
mustn't she have been fortifying?
mustn't we have been fortifying?
mustn't you have been fortifying?
mustn't they have been fortifying?