I must weld you must weld he must weld we must weld you must weld they must weld
Forme en V-ing
I must be welding you must be welding he must be welding we must be welding you must be welding they must be welding
Perfect
I must have welded you must have welded he must have welded we must have welded you must have welded they must have welded
Perfect en V-ing
I must have been welding you must have been welding he must have been welding we must have been welding you must have been welding they must have been welding
Négation
Forme simple
I mustn't weld you mustn't weld he mustn't weld we mustn't weld you mustn't weld they mustn't weld
Forme en V-ing
I mustn't be welding you mustn't be welding he mustn't be welding we mustn't be welding you mustn't be welding they mustn't be welding
Perfect
I mustn't have welded you mustn't have welded he mustn't have welded we mustn't have welded you mustn't have welded they mustn't have welded
Perfect en V-ing
I mustn't have been welding you mustn't have been welding he mustn't have been welding we mustn't have been welding you mustn't have been welding they mustn't have been welding
Forme interrogative
Forme simple
must I weld? must you weld? must he weld? must we weld? must you weld? must they weld?
Forme en V-ing
must I be welding? must you be welding? must he be welding? must we be welding? must you be welding? must they be welding?
Perfect
must I have welded? must you have welded? must he have welded? must we have welded? must you have welded? must they have welded?
Perfect en V-ing
must I have been welding? must you have been welding? must he have been welding? must we have been welding? must you have been welding? must they have been welding?
Forme interro-négative
Forme simple
mustn't I weld? mustn't you weld? mustn't he weld? mustn't we weld? mustn't you weld? mustn't they weld?
Forme en V-ing
mustn't I be welding? mustn't you be welding? mustn't he be welding? mustn't we be welding? mustn't you be welding? mustn't they be welding?
Perfect
mustn't I have welded? mustn't you have welded? mustn't he have welded? mustn't we have welded? mustn't you have welded? mustn't they have welded?
Perfect en V-ing
mustn't I have been welding? mustn't you have been welding? mustn't he have been welding? mustn't we have been welding? mustn't you have been welding? mustn't they have been welding?