must develop
Regular verb: develop - developed- developed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must develop
you must develop
she must develop
we must develop
you must develop
they must develop 	I must be developing
you must be developing
she must be developing
we must be developing
you must be developing
they must be developing	I must have developed
you must have developed
she must have developed
we must have developed
you must have developed
they must have developed	I must have been developing
you must have been developing
she must have been developing
we must have been developing
you must have been developing
they must have been developing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not develop
you must not develop
she must not develop
we must not develop
you must not develop
they must not develop 	I must not be developing
you must not be developing
she must not be developing
we must not be developing
you must not be developing
they must not be developing	I must not have developed
you must not have developed
she must not have developed
we must not have developed
you must not have developed
they must not have developed	I must not have been developing
you must not have been developing
she must not have been developing
we must not have been developing
you must not have been developing
they must not have been developing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I develop?
must you develop?
must she develop?
must we develop?
must you develop?
must they develop? 	must I be developing?
must you be developing?
must she be developing?
must we be developing?
must you be developing?
must they be developing? 	must I have developed?
must you have developed?
must she have developed?
must we have developed?
must you have developed?
must they have developed? 	must I have been developing?
must you have been developing?
must she have been developing?
must we have been developing?
must you have been developing?
must they have been developing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not develop?
must you not develop?
must she not develop?
must we not develop?
must you not develop?
must they not develop? 	must I not be developing?
must you not be developing?
must she not be developing?
must we not be developing?
must you not be developing?
must they not be developing? 	must I not have developed?
must you not have developed?
must she not have developed?
must we not have developed?
must you not have developed?
must they not have developed? 	must I not have been developing?
must you not have been developing?
must she not have been developing?
must we not have been developing?
must you not have been developing?
must they not have been developing?