must ko
Regular verb: ko - koed- koed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must ko
you must ko
he must ko
we must ko
you must ko
they must ko 	I must be koing
you must be koing
he must be koing
we must be koing
you must be koing
they must be koing	I must have koed
you must have koed
he must have koed
we must have koed
you must have koed
they must have koed	I must have been koing
you must have been koing
he must have been koing
we must have been koing
you must have been koing
they must have been koing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't ko
you mustn't ko
he mustn't ko
we mustn't ko
you mustn't ko
they mustn't ko 	I mustn't be koing
you mustn't be koing
he mustn't be koing
we mustn't be koing
you mustn't be koing
they mustn't be koing	I mustn't have koed
you mustn't have koed
he mustn't have koed
we mustn't have koed
you mustn't have koed
they mustn't have koed	I mustn't have been koing
you mustn't have been koing
he mustn't have been koing
we mustn't have been koing
you mustn't have been koing
they mustn't have been koing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I ko?
must you ko?
must he ko?
must we ko?
must you ko?
must they ko? 	must I be koing?
must you be koing?
must he be koing?
must we be koing?
must you be koing?
must they be koing? 	must I have koed?
must you have koed?
must he have koed?
must we have koed?
must you have koed?
must they have koed? 	must I have been koing?
must you have been koing?
must he have been koing?
must we have been koing?
must you have been koing?
must they have been koing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I ko?
mustn't you ko?
mustn't he ko?
mustn't we ko?
mustn't you ko?
mustn't they ko? 	mustn't I be koing?
mustn't you be koing?
mustn't he be koing?
mustn't we be koing?
mustn't you be koing?
mustn't they be koing? 	mustn't I have koed?
mustn't you have koed?
mustn't he have koed?
mustn't we have koed?
mustn't you have koed?
mustn't they have koed? 	mustn't I have been koing?
mustn't you have been koing?
mustn't he have been koing?
mustn't we have been koing?
mustn't you have been koing?
mustn't they have been koing?