must discontinue
Regular verb: discontinue - discontinued- discontinued

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must discontinue
you must discontinue
she must discontinue
we must discontinue
you must discontinue
they must discontinue 	I must be discontinuing
you must be discontinuing
she must be discontinuing
we must be discontinuing
you must be discontinuing
they must be discontinuing	I must have discontinued
you must have discontinued
she 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
she 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 mustn't discontinue
you mustn't discontinue
she mustn't discontinue
we mustn't discontinue
you mustn't discontinue
they mustn't discontinue 	I mustn't be discontinuing
you mustn't be discontinuing
she mustn't be discontinuing
we mustn't be discontinuing
you mustn't be discontinuing
they mustn't be discontinuing	I mustn't have discontinued
you mustn't have discontinued
she mustn't have discontinued
we mustn't have discontinued
you mustn't have discontinued
they mustn't have discontinued	I mustn't have been discontinuing
you mustn't have been discontinuing
she mustn't have been discontinuing
we mustn't have been discontinuing
you mustn't have been discontinuing
they mustn't have been discontinuing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I discontinue?
must you discontinue?
must she discontinue?
must we discontinue?
must you discontinue?
must they discontinue? 	must I be discontinuing?
must you be discontinuing?
must she be discontinuing?
must we be discontinuing?
must you be discontinuing?
must they be discontinuing? 	must I have discontinued?
must you have discontinued?
must she 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 she 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 	
mustn't I discontinue?
mustn't you discontinue?
mustn't she discontinue?
mustn't we discontinue?
mustn't you discontinue?
mustn't they discontinue? 	mustn't I be discontinuing?
mustn't you be discontinuing?
mustn't she be discontinuing?
mustn't we be discontinuing?
mustn't you be discontinuing?
mustn't they be discontinuing? 	mustn't I have discontinued?
mustn't you have discontinued?
mustn't she have discontinued?
mustn't we have discontinued?
mustn't you have discontinued?
mustn't they have discontinued? 	mustn't I have been discontinuing?
mustn't you have been discontinuing?
mustn't she have been discontinuing?
mustn't we have been discontinuing?
mustn't you have been discontinuing?
mustn't they have been discontinuing?