I must engineer you must engineer he must engineer we must engineer you must engineer they must engineer
Forma con V-ing
I must be engineering you must be engineering he must be engineering we must be engineering you must be engineering they must be engineering
Perfecto
I must have engineered you must have engineered he must have engineered we must have engineered you must have engineered they must have engineered
Perfecto con V-ing
I must have been engineering you must have been engineering he must have been engineering we must have been engineering you must have been engineering they must have been engineering
Negación
Forma simple
I must not engineer you must not engineer he must not engineer we must not engineer you must not engineer they must not engineer
Forma con V-ing
I must not be engineering you must not be engineering he must not be engineering we must not be engineering you must not be engineering they must not be engineering
Perfecto
I must not have engineered you must not have engineered he must not have engineered we must not have engineered you must not have engineered they must not have engineered
Perfecto con V-ing
I must not have been engineering you must not have been engineering he must not have been engineering we must not have been engineering you must not have been engineering they must not have been engineering
Forma interrogativa
Forma simple
must I engineer? must you engineer? must he engineer? must we engineer? must you engineer? must they engineer?
Forma con V-ing
must I be engineering? must you be engineering? must he be engineering? must we be engineering? must you be engineering? must they be engineering?
Perfecto
must I have engineered? must you have engineered? must he have engineered? must we have engineered? must you have engineered? must they have engineered?
Perfecto con V-ing
must I have been engineering? must you have been engineering? must he have been engineering? must we have been engineering? must you have been engineering? must they have been engineering?
Forma interro-negativa
Forma simple
must I not engineer? must you not engineer? must he not engineer? must we not engineer? must you not engineer? must they not engineer?
Forma con V-ing
must I not be engineering? must you not be engineering? must he not be engineering? must we not be engineering? must you not be engineering? must they not be engineering?
Perfecto
must I not have engineered? must you not have engineered? must he not have engineered? must we not have engineered? must you not have engineered? must they not have engineered?
Perfecto con V-ing
must I not have been engineering? must you not have been engineering? must he not have been engineering? must we not have been engineering? must you not have been engineering? must they not have been engineering?