I must bur you must bur he must bur we must bur you must bur they must bur
Forma con V-ing
I must be buring you must be buring he must be buring we must be buring you must be buring they must be buring
Perfecto
I must have bured you must have bured he must have bured we must have bured you must have bured they must have bured
Perfecto con V-ing
I must have been buring you must have been buring he must have been buring we must have been buring you must have been buring they must have been buring
Negación
Forma simple
I must not bur you must not bur he must not bur we must not bur you must not bur they must not bur
Forma con V-ing
I must not be buring you must not be buring he must not be buring we must not be buring you must not be buring they must not be buring
Perfecto
I must not have bured you must not have bured he must not have bured we must not have bured you must not have bured they must not have bured
Perfecto con V-ing
I must not have been buring you must not have been buring he must not have been buring we must not have been buring you must not have been buring they must not have been buring
Forma interrogativa
Forma simple
must I bur? must you bur? must he bur? must we bur? must you bur? must they bur?
Forma con V-ing
must I be buring? must you be buring? must he be buring? must we be buring? must you be buring? must they be buring?
Perfecto
must I have bured? must you have bured? must he have bured? must we have bured? must you have bured? must they have bured?
Perfecto con V-ing
must I have been buring? must you have been buring? must he have been buring? must we have been buring? must you have been buring? must they have been buring?
Forma interro-negativa
Forma simple
must I not bur? must you not bur? must he not bur? must we not bur? must you not bur? must they not bur?
Forma con V-ing
must I not be buring? must you not be buring? must he not be buring? must we not be buring? must you not be buring? must they not be buring?
Perfecto
must I not have bured? must you not have bured? must he not have bured? must we not have bured? must you not have bured? must they not have bured?
Perfecto con V-ing
must I not have been buring? must you not have been buring? must he not have been buring? must we not have been buring? must you not have been buring? must they not have been buring?