must detain
Regular verb: detain - detained- detained

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must detain
you must detain
she must detain
we must detain
you must detain
they must detain 	I must be detaining
you must be detaining
she must be detaining
we must be detaining
you must be detaining
they must be detaining	I must have detained
you must have detained
she must have detained
we must have detained
you must have detained
they must have detained	I must have been detaining
you must have been detaining
she must have been detaining
we must have been detaining
you must have been detaining
they must have been detaining	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't detain
you mustn't detain
she mustn't detain
we mustn't detain
you mustn't detain
they mustn't detain 	I mustn't be detaining
you mustn't be detaining
she mustn't be detaining
we mustn't be detaining
you mustn't be detaining
they mustn't be detaining	I mustn't have detained
you mustn't have detained
she mustn't have detained
we mustn't have detained
you mustn't have detained
they mustn't have detained	I mustn't have been detaining
you mustn't have been detaining
she mustn't have been detaining
we mustn't have been detaining
you mustn't have been detaining
they mustn't have been detaining	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I detain?
must you detain?
must she detain?
must we detain?
must you detain?
must they detain? 	must I be detaining?
must you be detaining?
must she be detaining?
must we be detaining?
must you be detaining?
must they be detaining? 	must I have detained?
must you have detained?
must she have detained?
must we have detained?
must you have detained?
must they have detained? 	must I have been detaining?
must you have been detaining?
must she have been detaining?
must we have been detaining?
must you have been detaining?
must they have been detaining? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I detain?
mustn't you detain?
mustn't she detain?
mustn't we detain?
mustn't you detain?
mustn't they detain? 	mustn't I be detaining?
mustn't you be detaining?
mustn't she be detaining?
mustn't we be detaining?
mustn't you be detaining?
mustn't they be detaining? 	mustn't I have detained?
mustn't you have detained?
mustn't she have detained?
mustn't we have detained?
mustn't you have detained?
mustn't they have detained? 	mustn't I have been detaining?
mustn't you have been detaining?
mustn't she have been detaining?
mustn't we have been detaining?
mustn't you have been detaining?
mustn't they have been detaining?