I must knock you must knock he must knock we must knock you must knock they must knock
Forma con V-ing
I must be knocking you must be knocking he must be knocking we must be knocking you must be knocking they must be knocking
Perfecto
I must have knocked you must have knocked he must have knocked we must have knocked you must have knocked they must have knocked
Perfecto con V-ing
I must have been knocking you must have been knocking he must have been knocking we must have been knocking you must have been knocking they must have been knocking
Negación
Forma simple
I mustn't knock you mustn't knock he mustn't knock we mustn't knock you mustn't knock they mustn't knock
Forma con V-ing
I mustn't be knocking you mustn't be knocking he mustn't be knocking we mustn't be knocking you mustn't be knocking they mustn't be knocking
Perfecto
I mustn't have knocked you mustn't have knocked he mustn't have knocked we mustn't have knocked you mustn't have knocked they mustn't have knocked
Perfecto con V-ing
I mustn't have been knocking you mustn't have been knocking he mustn't have been knocking we mustn't have been knocking you mustn't have been knocking they mustn't have been knocking
Forma interrogativa
Forma simple
must I knock? must you knock? must he knock? must we knock? must you knock? must they knock?
Forma con V-ing
must I be knocking? must you be knocking? must he be knocking? must we be knocking? must you be knocking? must they be knocking?
Perfecto
must I have knocked? must you have knocked? must he have knocked? must we have knocked? must you have knocked? must they have knocked?
Perfecto con V-ing
must I have been knocking? must you have been knocking? must he have been knocking? must we have been knocking? must you have been knocking? must they have been knocking?
Forma interro-negativa
Forma simple
mustn't I knock? mustn't you knock? mustn't he knock? mustn't we knock? mustn't you knock? mustn't they knock?
Forma con V-ing
mustn't I be knocking? mustn't you be knocking? mustn't he be knocking? mustn't we be knocking? mustn't you be knocking? mustn't they be knocking?
Perfecto
mustn't I have knocked? mustn't you have knocked? mustn't he have knocked? mustn't we have knocked? mustn't you have knocked? mustn't they have knocked?
Perfecto con V-ing
mustn't I have been knocking? mustn't you have been knocking? mustn't he have been knocking? mustn't we have been knocking? mustn't you have been knocking? mustn't they have been knocking?