I must guard you must guard he must guard we must guard you must guard they must guard
Forma con V-ing
I must be guarding you must be guarding he must be guarding we must be guarding you must be guarding they must be guarding
Perfecto
I must have guarded you must have guarded he must have guarded we must have guarded you must have guarded they must have guarded
Perfecto con V-ing
I must have been guarding you must have been guarding he must have been guarding we must have been guarding you must have been guarding they must have been guarding
Negación
Forma simple
I must not guard you must not guard he must not guard we must not guard you must not guard they must not guard
Forma con V-ing
I must not be guarding you must not be guarding he must not be guarding we must not be guarding you must not be guarding they must not be guarding
Perfecto
I must not have guarded you must not have guarded he must not have guarded we must not have guarded you must not have guarded they must not have guarded
Perfecto con V-ing
I must not have been guarding you must not have been guarding he must not have been guarding we must not have been guarding you must not have been guarding they must not have been guarding
Forma interrogativa
Forma simple
must I guard? must you guard? must he guard? must we guard? must you guard? must they guard?
Forma con V-ing
must I be guarding? must you be guarding? must he be guarding? must we be guarding? must you be guarding? must they be guarding?
Perfecto
must I have guarded? must you have guarded? must he have guarded? must we have guarded? must you have guarded? must they have guarded?
Perfecto con V-ing
must I have been guarding? must you have been guarding? must he have been guarding? must we have been guarding? must you have been guarding? must they have been guarding?
Forma interro-negativa
Forma simple
must I not guard? must you not guard? must he not guard? must we not guard? must you not guard? must they not guard?
Forma con V-ing
must I not be guarding? must you not be guarding? must he not be guarding? must we not be guarding? must you not be guarding? must they not be guarding?
Perfecto
must I not have guarded? must you not have guarded? must he not have guarded? must we not have guarded? must you not have guarded? must they not have guarded?
Perfecto con V-ing
must I not have been guarding? must you not have been guarding? must he not have been guarding? must we not have been guarding? must you not have been guarding? must they not have been guarding?