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