I must form you must form he must form we must form you must form they must form
Forma con V-ing
I must be forming you must be forming he must be forming we must be forming you must be forming they must be forming
Perfecto
I must have formed you must have formed he must have formed we must have formed you must have formed they must have formed
Perfecto con V-ing
I must have been forming you must have been forming he must have been forming we must have been forming you must have been forming they must have been forming
Negación
Forma simple
I mustn't form you mustn't form he mustn't form we mustn't form you mustn't form they mustn't form
Forma con V-ing
I mustn't be forming you mustn't be forming he mustn't be forming we mustn't be forming you mustn't be forming they mustn't be forming
Perfecto
I mustn't have formed you mustn't have formed he mustn't have formed we mustn't have formed you mustn't have formed they mustn't have formed
Perfecto con V-ing
I mustn't have been forming you mustn't have been forming he mustn't have been forming we mustn't have been forming you mustn't have been forming they mustn't have been forming
Forma interrogativa
Forma simple
must I form? must you form? must he form? must we form? must you form? must they form?
Forma con V-ing
must I be forming? must you be forming? must he be forming? must we be forming? must you be forming? must they be forming?
Perfecto
must I have formed? must you have formed? must he have formed? must we have formed? must you have formed? must they have formed?
Perfecto con V-ing
must I have been forming? must you have been forming? must he have been forming? must we have been forming? must you have been forming? must they have been forming?
Forma interro-negativa
Forma simple
mustn't I form? mustn't you form? mustn't he form? mustn't we form? mustn't you form? mustn't they form?
Forma con V-ing
mustn't I be forming? mustn't you be forming? mustn't he be forming? mustn't we be forming? mustn't you be forming? mustn't they be forming?
Perfecto
mustn't I have formed? mustn't you have formed? mustn't he have formed? mustn't we have formed? mustn't you have formed? mustn't they have formed?
Perfecto con V-ing
mustn't I have been forming? mustn't you have been forming? mustn't he have been forming? mustn't we have been forming? mustn't you have been forming? mustn't they have been forming?