must discontinue
Regular verb: discontinue - discontinued- discontinued

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must discontinue
you must discontinue
he must discontinue
we must discontinue
you must discontinue
they must discontinue 	I must be discontinuing
you must be discontinuing
he must be discontinuing
we must be discontinuing
you must be discontinuing
they must be discontinuing	I must have discontinued
you must have discontinued
he must have discontinued
we must have discontinued
you must have discontinued
they must have discontinued	I must have been discontinuing
you must have been discontinuing
he must have been discontinuing
we must have been discontinuing
you must have been discontinuing
they must have been discontinuing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not discontinue
you must not discontinue
he must not discontinue
we must not discontinue
you must not discontinue
they must not discontinue 	I must not be discontinuing
you must not be discontinuing
he must not be discontinuing
we must not be discontinuing
you must not be discontinuing
they must not be discontinuing	I must not have discontinued
you must not have discontinued
he must not have discontinued
we must not have discontinued
you must not have discontinued
they must not have discontinued	I must not have been discontinuing
you must not have been discontinuing
he must not have been discontinuing
we must not have been discontinuing
you must not have been discontinuing
they must not have been discontinuing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I discontinue?
must you discontinue?
must he discontinue?
must we discontinue?
must you discontinue?
must they discontinue? 	must I be discontinuing?
must you be discontinuing?
must he be discontinuing?
must we be discontinuing?
must you be discontinuing?
must they be discontinuing? 	must I have discontinued?
must you have discontinued?
must he have discontinued?
must we have discontinued?
must you have discontinued?
must they have discontinued? 	must I have been discontinuing?
must you have been discontinuing?
must he have been discontinuing?
must we have been discontinuing?
must you have been discontinuing?
must they have been discontinuing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not discontinue?
must you not discontinue?
must he not discontinue?
must we not discontinue?
must you not discontinue?
must they not discontinue? 	must I not be discontinuing?
must you not be discontinuing?
must he not be discontinuing?
must we not be discontinuing?
must you not be discontinuing?
must they not be discontinuing? 	must I not have discontinued?
must you not have discontinued?
must he not have discontinued?
must we not have discontinued?
must you not have discontinued?
must they not have discontinued? 	must I not have been discontinuing?
must you not have been discontinuing?
must he not have been discontinuing?
must we not have been discontinuing?
must you not have been discontinuing?
must they not have been discontinuing?