I must twist you must twist he must twist we must twist you must twist they must twist
V-ing form
I must be twisting you must be twisting he must be twisting we must be twisting you must be twisting they must be twisting
Perfect
I must have twisted you must have twisted he must have twisted we must have twisted you must have twisted they must have twisted
V-ing perfect
I must have been twisting you must have been twisting he must have been twisting we must have been twisting you must have been twisting they must have been twisting
Negation
Simple form
I mustn't twist you mustn't twist he mustn't twist we mustn't twist you mustn't twist they mustn't twist
V-ing form
I mustn't be twisting you mustn't be twisting he mustn't be twisting we mustn't be twisting you mustn't be twisting they mustn't be twisting
Perfect
I mustn't have twisted you mustn't have twisted he mustn't have twisted we mustn't have twisted you mustn't have twisted they mustn't have twisted
V-ing perfect
I mustn't have been twisting you mustn't have been twisting he mustn't have been twisting we mustn't have been twisting you mustn't have been twisting they mustn't have been twisting
Interrogative form
Simple form
must I twist? must you twist? must he twist? must we twist? must you twist? must they twist?
V-ing form
must I be twisting? must you be twisting? must he be twisting? must we be twisting? must you be twisting? must they be twisting?
Perfect
must I have twisted? must you have twisted? must he have twisted? must we have twisted? must you have twisted? must they have twisted?
V-ing perfect
must I have been twisting? must you have been twisting? must he have been twisting? must we have been twisting? must you have been twisting? must they have been twisting?
Interro-negative form
Simple form
mustn't I twist? mustn't you twist? mustn't he twist? mustn't we twist? mustn't you twist? mustn't they twist?
V-ing form
mustn't I be twisting? mustn't you be twisting? mustn't he be twisting? mustn't we be twisting? mustn't you be twisting? mustn't they be twisting?
Perfect
mustn't I have twisted? mustn't you have twisted? mustn't he have twisted? mustn't we have twisted? mustn't you have twisted? mustn't they have twisted?
V-ing perfect
mustn't I have been twisting? mustn't you have been twisting? mustn't he have been twisting? mustn't we have been twisting? mustn't you have been twisting? mustn't they have been twisting?