English verb conjugation
MUST KNOCK

Regular verb: knock - knocked - knocked

Affirmation

Simple form	V-ing form
I must knock you must knock she must knock we must knock you must knock they must knock	I must be knocking you must be knocking she must be knocking we must be knocking you must be knocking they must be knocking
Perfect	V-ing perfect
I must have knocked you must have knocked she must have knocked we must have knocked you must have knocked they must have knocked	I must have been knocking you must have been knocking she must have been knocking we must have been knocking you must have been knocking they must have been knocking

Negation

Simple form	V-ing form
I mustn't knock you mustn't knock she mustn't knock we mustn't knock you mustn't knock they mustn't knock	I mustn't be knocking you mustn't be knocking she mustn't be knocking we mustn't be knocking you mustn't be knocking they mustn't be knocking
Perfect	V-ing perfect
I mustn't have knocked you mustn't have knocked she mustn't have knocked we mustn't have knocked you mustn't have knocked they mustn't have knocked	I mustn't have been knocking you mustn't have been knocking she mustn't have been knocking we mustn't have been knocking you mustn't have been knocking they mustn't have been knocking

Interrogative form

Simple form	V-ing form
must I knock? must you knock? must she knock? must we knock? must you knock? must they knock?	must I be knocking? must you be knocking? must she be knocking? must we be knocking? must you be knocking? must they be knocking?
Perfect	V-ing perfect
must I have knocked? must you have knocked? must she have knocked? must we have knocked? must you have knocked? must they have knocked?	must I have been knocking? must you have been knocking? must she have been knocking? must we have been knocking? must you have been knocking? must they have been knocking?

Interro-negative form

Simple form	V-ing form
mustn't I knock? mustn't you knock? mustn't she knock? mustn't we knock? mustn't you knock? mustn't they knock?	mustn't I be knocking? mustn't you be knocking? mustn't she be knocking? mustn't we be knocking? mustn't you be knocking? mustn't they be knocking?
Perfect	V-ing perfect
mustn't I have knocked? mustn't you have knocked? mustn't she have knocked? mustn't we have knocked? mustn't you have knocked? mustn't they have knocked?	mustn't I have been knocking? mustn't you have been knocking? mustn't she have been knocking? mustn't we have been knocking? mustn't you have been knocking? mustn't they have been knocking?