I must spring you must spring he must spring we must spring you must spring they must spring
Forma con V-ing
I must be springing you must be springing he must be springing we must be springing you must be springing they must be springing
Perfecto
I must have sprung you must have sprung he must have sprung we must have sprung you must have sprung they must have sprung
Perfecto con V-ing
I must have been springing you must have been springing he must have been springing we must have been springing you must have been springing they must have been springing
Negación
Forma simple
I must not spring you must not spring he must not spring we must not spring you must not spring they must not spring
Forma con V-ing
I must not be springing you must not be springing he must not be springing we must not be springing you must not be springing they must not be springing
Perfecto
I must not have sprung you must not have sprung he must not have sprung we must not have sprung you must not have sprung they must not have sprung
Perfecto con V-ing
I must not have been springing you must not have been springing he must not have been springing we must not have been springing you must not have been springing they must not have been springing
Forma interrogativa
Forma simple
must I spring? must you spring? must he spring? must we spring? must you spring? must they spring?
Forma con V-ing
must I be springing? must you be springing? must he be springing? must we be springing? must you be springing? must they be springing?
Perfecto
must I have sprung? must you have sprung? must he have sprung? must we have sprung? must you have sprung? must they have sprung?
Perfecto con V-ing
must I have been springing? must you have been springing? must he have been springing? must we have been springing? must you have been springing? must they have been springing?
Forma interro-negativa
Forma simple
must I not spring? must you not spring? must he not spring? must we not spring? must you not spring? must they not spring?
Forma con V-ing
must I not be springing? must you not be springing? must he not be springing? must we not be springing? must you not be springing? must they not be springing?
Perfecto
must I not have sprung? must you not have sprung? must he not have sprung? must we not have sprung? must you not have sprung? must they not have sprung?
Perfecto con V-ing
must I not have been springing? must you not have been springing? must he not have been springing? must we not have been springing? must you not have been springing? must they not have been springing?