must undeceive
Regular verb: undeceive - undeceived- undeceived

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must undeceive
you must undeceive
he must undeceive
we must undeceive
you must undeceive
they must undeceive 	I must be undeceiving
you must be undeceiving
he must be undeceiving
we must be undeceiving
you must be undeceiving
they must be undeceiving	I must have undeceived
you must have undeceived
he must have undeceived
we must have undeceived
you must have undeceived
they must have undeceived	I must have been undeceiving
you must have been undeceiving
he must have been undeceiving
we must have been undeceiving
you must have been undeceiving
they must have been undeceiving	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't undeceive
you mustn't undeceive
he mustn't undeceive
we mustn't undeceive
you mustn't undeceive
they mustn't undeceive 	I mustn't be undeceiving
you mustn't be undeceiving
he mustn't be undeceiving
we mustn't be undeceiving
you mustn't be undeceiving
they mustn't be undeceiving	I mustn't have undeceived
you mustn't have undeceived
he mustn't have undeceived
we mustn't have undeceived
you mustn't have undeceived
they mustn't have undeceived	I mustn't have been undeceiving
you mustn't have been undeceiving
he mustn't have been undeceiving
we mustn't have been undeceiving
you mustn't have been undeceiving
they mustn't have been undeceiving	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I undeceive?
must you undeceive?
must he undeceive?
must we undeceive?
must you undeceive?
must they undeceive? 	must I be undeceiving?
must you be undeceiving?
must he be undeceiving?
must we be undeceiving?
must you be undeceiving?
must they be undeceiving? 	must I have undeceived?
must you have undeceived?
must he have undeceived?
must we have undeceived?
must you have undeceived?
must they have undeceived? 	must I have been undeceiving?
must you have been undeceiving?
must he have been undeceiving?
must we have been undeceiving?
must you have been undeceiving?
must they have been undeceiving? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I undeceive?
mustn't you undeceive?
mustn't he undeceive?
mustn't we undeceive?
mustn't you undeceive?
mustn't they undeceive? 	mustn't I be undeceiving?
mustn't you be undeceiving?
mustn't he be undeceiving?
mustn't we be undeceiving?
mustn't you be undeceiving?
mustn't they be undeceiving? 	mustn't I have undeceived?
mustn't you have undeceived?
mustn't he have undeceived?
mustn't we have undeceived?
mustn't you have undeceived?
mustn't they have undeceived? 	mustn't I have been undeceiving?
mustn't you have been undeceiving?
mustn't he have been undeceiving?
mustn't we have been undeceiving?
mustn't you have been undeceiving?
mustn't they have been undeceiving?