I must sire you must sire he must sire we must sire you must sire they must sire
Forma con V-ing
I must be siring you must be siring he must be siring we must be siring you must be siring they must be siring
Perfecto
I must have sired you must have sired he must have sired we must have sired you must have sired they must have sired
Perfecto con V-ing
I must have been siring you must have been siring he must have been siring we must have been siring you must have been siring they must have been siring
Negación
Forma simple
I must not sire you must not sire he must not sire we must not sire you must not sire they must not sire
Forma con V-ing
I must not be siring you must not be siring he must not be siring we must not be siring you must not be siring they must not be siring
Perfecto
I must not have sired you must not have sired he must not have sired we must not have sired you must not have sired they must not have sired
Perfecto con V-ing
I must not have been siring you must not have been siring he must not have been siring we must not have been siring you must not have been siring they must not have been siring
Forma interrogativa
Forma simple
must I sire? must you sire? must he sire? must we sire? must you sire? must they sire?
Forma con V-ing
must I be siring? must you be siring? must he be siring? must we be siring? must you be siring? must they be siring?
Perfecto
must I have sired? must you have sired? must he have sired? must we have sired? must you have sired? must they have sired?
Perfecto con V-ing
must I have been siring? must you have been siring? must he have been siring? must we have been siring? must you have been siring? must they have been siring?
Forma interro-negativa
Forma simple
must I not sire? must you not sire? must he not sire? must we not sire? must you not sire? must they not sire?
Forma con V-ing
must I not be siring? must you not be siring? must he not be siring? must we not be siring? must you not be siring? must they not be siring?
Perfecto
must I not have sired? must you not have sired? must he not have sired? must we not have sired? must you not have sired? must they not have sired?
Perfecto con V-ing
must I not have been siring? must you not have been siring? must he not have been siring? must we not have been siring? must you not have been siring? must they not have been siring?