I must sustain you must sustain she must sustain we must sustain you must sustain they must sustain
Forma com 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
Perfeito
I must have sustained you must have sustained she must have sustained we must have sustained you must have sustained they must have sustained
Perfeito com 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
Negação
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 com 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
Perfeito
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
Perfeito com 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 com 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?
Perfeito
must I have sustained? must you have sustained? must she have sustained? must we have sustained? must you have sustained? must they have sustained?
Perfeito com 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-Negação
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 com 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?
Perfeito
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?
Perfeito com 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?