Attention, ce verbe peut ne pas exister, la conjugaison est donnée à titre d'exemple.
Affirmation
Forme simple
I must stiffer you must stiffer she must stiffer we must stiffer you must stiffer they must stiffer
Forme en V-ing
I must be stiffering you must be stiffering she must be stiffering we must be stiffering you must be stiffering they must be stiffering
Perfect
I must have stiffered you must have stiffered she must have stiffered we must have stiffered you must have stiffered they must have stiffered
Perfect en V-ing
I must have been stiffering you must have been stiffering she must have been stiffering we must have been stiffering you must have been stiffering they must have been stiffering
Négation
Forme simple
I mustn't stiffer you mustn't stiffer she mustn't stiffer we mustn't stiffer you mustn't stiffer they mustn't stiffer
Forme en V-ing
I mustn't be stiffering you mustn't be stiffering she mustn't be stiffering we mustn't be stiffering you mustn't be stiffering they mustn't be stiffering
Perfect
I mustn't have stiffered you mustn't have stiffered she mustn't have stiffered we mustn't have stiffered you mustn't have stiffered they mustn't have stiffered
Perfect en V-ing
I mustn't have been stiffering you mustn't have been stiffering she mustn't have been stiffering we mustn't have been stiffering you mustn't have been stiffering they mustn't have been stiffering
Forme interrogative
Forme simple
must I stiffer? must you stiffer? must she stiffer? must we stiffer? must you stiffer? must they stiffer?
Forme en V-ing
must I be stiffering? must you be stiffering? must she be stiffering? must we be stiffering? must you be stiffering? must they be stiffering?
Perfect
must I have stiffered? must you have stiffered? must she have stiffered? must we have stiffered? must you have stiffered? must they have stiffered?
Perfect en V-ing
must I have been stiffering? must you have been stiffering? must she have been stiffering? must we have been stiffering? must you have been stiffering? must they have been stiffering?
Forme interro-négative
Forme simple
mustn't I stiffer? mustn't you stiffer? mustn't she stiffer? mustn't we stiffer? mustn't you stiffer? mustn't they stiffer?
Forme en V-ing
mustn't I be stiffering? mustn't you be stiffering? mustn't she be stiffering? mustn't we be stiffering? mustn't you be stiffering? mustn't they be stiffering?
Perfect
mustn't I have stiffered? mustn't you have stiffered? mustn't she have stiffered? mustn't we have stiffered? mustn't you have stiffered? mustn't they have stiffered?
Perfect en V-ing
mustn't I have been stiffering? mustn't you have been stiffering? mustn't she have been stiffering? mustn't we have been stiffering? mustn't you have been stiffering? mustn't they have been stiffering?