must restack
Regular verb: restack - restacked- restacked

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must restack
you must restack
she must restack
we must restack
you must restack
they must restack 	I must be restacking
you must be restacking
she must be restacking
we must be restacking
you must be restacking
they must be restacking	I must have restacked
you must have restacked
she must have restacked
we must have restacked
you must have restacked
they must have restacked	I must have been restacking
you must have been restacking
she must have been restacking
we must have been restacking
you must have been restacking
they must have been restacking	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't restack
you mustn't restack
she mustn't restack
we mustn't restack
you mustn't restack
they mustn't restack 	I mustn't be restacking
you mustn't be restacking
she mustn't be restacking
we mustn't be restacking
you mustn't be restacking
they mustn't be restacking	I mustn't have restacked
you mustn't have restacked
she mustn't have restacked
we mustn't have restacked
you mustn't have restacked
they mustn't have restacked	I mustn't have been restacking
you mustn't have been restacking
she mustn't have been restacking
we mustn't have been restacking
you mustn't have been restacking
they mustn't have been restacking	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I restack?
must you restack?
must she restack?
must we restack?
must you restack?
must they restack? 	must I be restacking?
must you be restacking?
must she be restacking?
must we be restacking?
must you be restacking?
must they be restacking? 	must I have restacked?
must you have restacked?
must she have restacked?
must we have restacked?
must you have restacked?
must they have restacked? 	must I have been restacking?
must you have been restacking?
must she have been restacking?
must we have been restacking?
must you have been restacking?
must they have been restacking? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I restack?
mustn't you restack?
mustn't she restack?
mustn't we restack?
mustn't you restack?
mustn't they restack? 	mustn't I be restacking?
mustn't you be restacking?
mustn't she be restacking?
mustn't we be restacking?
mustn't you be restacking?
mustn't they be restacking? 	mustn't I have restacked?
mustn't you have restacked?
mustn't she have restacked?
mustn't we have restacked?
mustn't you have restacked?
mustn't they have restacked? 	mustn't I have been restacking?
mustn't you have been restacking?
mustn't she have been restacking?
mustn't we have been restacking?
mustn't you have been restacking?
mustn't they have been restacking?