English verb conjugation
SHOULD KNOCK

Regular verb: knock - knocked - knocked

Affirmation

Simple form	V-ing form
I'd knock you'd knock he'd knock we'd knock you'd knock they'd knock	I'd be knocking you'd be knocking he'd be knocking we'd be knocking you'd be knocking they'd be knocking
Perfect	V-ing perfect
I should've knocked you should've knocked he should've knocked we should've knocked you should've knocked they should've knocked	I should've been knocking you should've been knocking he should've been knocking we should've been knocking you should've been knocking they should've been knocking

Negation

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

Interrogative form

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

Interro-negative form

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