must defer
Regular verb: defer - deferred- deferred

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must defer
you must defer
she must defer
we must defer
you must defer
they must defer 	I must be deferring
you must be deferring
she must be deferring
we must be deferring
you must be deferring
they must be deferring	I must have deferred
you must have deferred
she must have deferred
we must have deferred
you must have deferred
they must have deferred	I must have been deferring
you must have been deferring
she must have been deferring
we must have been deferring
you must have been deferring
they must have been deferring	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't defer
you mustn't defer
she mustn't defer
we mustn't defer
you mustn't defer
they mustn't defer 	I mustn't be deferring
you mustn't be deferring
she mustn't be deferring
we mustn't be deferring
you mustn't be deferring
they mustn't be deferring	I mustn't have deferred
you mustn't have deferred
she mustn't have deferred
we mustn't have deferred
you mustn't have deferred
they mustn't have deferred	I mustn't have been deferring
you mustn't have been deferring
she mustn't have been deferring
we mustn't have been deferring
you mustn't have been deferring
they mustn't have been deferring	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I defer?
must you defer?
must she defer?
must we defer?
must you defer?
must they defer? 	must I be deferring?
must you be deferring?
must she be deferring?
must we be deferring?
must you be deferring?
must they be deferring? 	must I have deferred?
must you have deferred?
must she have deferred?
must we have deferred?
must you have deferred?
must they have deferred? 	must I have been deferring?
must you have been deferring?
must she have been deferring?
must we have been deferring?
must you have been deferring?
must they have been deferring? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I defer?
mustn't you defer?
mustn't she defer?
mustn't we defer?
mustn't you defer?
mustn't they defer? 	mustn't I be deferring?
mustn't you be deferring?
mustn't she be deferring?
mustn't we be deferring?
mustn't you be deferring?
mustn't they be deferring? 	mustn't I have deferred?
mustn't you have deferred?
mustn't she have deferred?
mustn't we have deferred?
mustn't you have deferred?
mustn't they have deferred? 	mustn't I have been deferring?
mustn't you have been deferring?
mustn't she have been deferring?
mustn't we have been deferring?
mustn't you have been deferring?
mustn't they have been deferring?