I must weld you must weld she must weld we must weld you must weld they must weld
Forma con V-ing
I must be welding you must be welding she must be welding we must be welding you must be welding they must be welding
Perfecto
I must have welded you must have welded she must have welded we must have welded you must have welded they must have welded
Perfecto con V-ing
I must have been welding you must have been welding she must have been welding we must have been welding you must have been welding they must have been welding
Negación
Forma simple
I mustn't weld you mustn't weld she mustn't weld we mustn't weld you mustn't weld they mustn't weld
Forma con V-ing
I mustn't be welding you mustn't be welding she mustn't be welding we mustn't be welding you mustn't be welding they mustn't be welding
Perfecto
I mustn't have welded you mustn't have welded she mustn't have welded we mustn't have welded you mustn't have welded they mustn't have welded
Perfecto con V-ing
I mustn't have been welding you mustn't have been welding she mustn't have been welding we mustn't have been welding you mustn't have been welding they mustn't have been welding
Forma interrogativa
Forma simple
must I weld? must you weld? must she weld? must we weld? must you weld? must they weld?
Forma con V-ing
must I be welding? must you be welding? must she be welding? must we be welding? must you be welding? must they be welding?
Perfecto
must I have welded? must you have welded? must she have welded? must we have welded? must you have welded? must they have welded?
Perfecto con V-ing
must I have been welding? must you have been welding? must she have been welding? must we have been welding? must you have been welding? must they have been welding?
Forma interro-negativa
Forma simple
mustn't I weld? mustn't you weld? mustn't she weld? mustn't we weld? mustn't you weld? mustn't they weld?
Forma con V-ing
mustn't I be welding? mustn't you be welding? mustn't she be welding? mustn't we be welding? mustn't you be welding? mustn't they be welding?
Perfecto
mustn't I have welded? mustn't you have welded? mustn't she have welded? mustn't we have welded? mustn't you have welded? mustn't they have welded?
Perfecto con V-ing
mustn't I have been welding? mustn't you have been welding? mustn't she have been welding? mustn't we have been welding? mustn't you have been welding? mustn't they have been welding?