I must keep you must keep she must keep we must keep you must keep they must keep
Forma con V-ing
I must be keeping you must be keeping she must be keeping we must be keeping you must be keeping they must be keeping
Perfecto
I must have kept you must have kept she must have kept we must have kept you must have kept they must have kept
Perfecto con V-ing
I must have been keeping you must have been keeping she must have been keeping we must have been keeping you must have been keeping they must have been keeping
Negación
Forma simple
I must not keep you must not keep she must not keep we must not keep you must not keep they must not keep
Forma con V-ing
I must not be keeping you must not be keeping she must not be keeping we must not be keeping you must not be keeping they must not be keeping
Perfecto
I must not have kept you must not have kept she must not have kept we must not have kept you must not have kept they must not have kept
Perfecto con V-ing
I must not have been keeping you must not have been keeping she must not have been keeping we must not have been keeping you must not have been keeping they must not have been keeping
Forma interrogativa
Forma simple
must I keep? must you keep? must she keep? must we keep? must you keep? must they keep?
Forma con V-ing
must I be keeping? must you be keeping? must she be keeping? must we be keeping? must you be keeping? must they be keeping?
Perfecto
must I have kept? must you have kept? must she have kept? must we have kept? must you have kept? must they have kept?
Perfecto con V-ing
must I have been keeping? must you have been keeping? must she have been keeping? must we have been keeping? must you have been keeping? must they have been keeping?
Forma interro-negativa
Forma simple
must I not keep? must you not keep? must she not keep? must we not keep? must you not keep? must they not keep?
Forma con V-ing
must I not be keeping? must you not be keeping? must she not be keeping? must we not be keeping? must you not be keeping? must they not be keeping?
Perfecto
must I not have kept? must you not have kept? must she not have kept? must we not have kept? must you not have kept? must they not have kept?
Perfecto con V-ing
must I not have been keeping? must you not have been keeping? must she not have been keeping? must we not have been keeping? must you not have been keeping? must they not have been keeping?