English verb conjugation
COULD KNOCK KNOCK

Regular verb: knock knock - knock knocked - knock knocked

Warning, this verb may not exist. Conjugation is given as example.

Affirmation

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

Negation

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

Interrogative form

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

Interro-negative form

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