Conjugación del verbo inglés
COULD KNOCK

Verbo regular: knock - knocked - knocked

Afirmación

Forma simple	Forma con V-ing
I could knock you could knock he could knock we could knock you could knock they could knock	I could be knocking you could be knocking he could be knocking we could be knocking you could be knocking they could be knocking
Perfecto	Perfecto con V-ing
I could have knocked you could have knocked he could have knocked we could have knocked you could have knocked they could have knocked	I could have been knocking you could have been knocking he could have been knocking we could have been knocking you could have been knocking they could have been knocking

Negación

Forma simple	Forma con V-ing
I couldn't knock you couldn't knock he couldn't knock we couldn't knock you couldn't knock they couldn't knock	I couldn't be knocking you couldn't be knocking he couldn't be knocking we couldn't be knocking you couldn't be knocking they couldn't be knocking
Perfecto	Perfecto con V-ing
I couldn't have knocked you couldn't have knocked he couldn't have knocked we couldn't have knocked you couldn't have knocked they couldn't have knocked	I couldn't have been knocking you couldn't have been knocking he couldn't have been knocking we couldn't have been knocking you couldn't have been knocking they couldn't have been knocking

Forma interrogativa

Forma simple	Forma con V-ing
could I knock? could you knock? could he knock? could we knock? could you knock? could they knock?	could I be knocking? could you be knocking? could he be knocking? could we be knocking? could you be knocking? could they be knocking?
Perfecto	Perfecto con V-ing
could I have knocked? could you have knocked? could he have knocked? could we have knocked? could you have knocked? could they have knocked?	could I have been knocking? could you have been knocking? could he have been knocking? could we have been knocking? could you have been knocking? could they have been knocking?

Forma interro-negativa

Forma simple	Forma con V-ing
couldn't I knock? couldn't you knock? couldn't he knock? couldn't we knock? couldn't you knock? couldn't they knock?	couldn't I be knocking? couldn't you be knocking? couldn't he be knocking? couldn't we be knocking? couldn't you be knocking? couldn't they be knocking?
Perfecto	Perfecto con V-ing
couldn't I have knocked? couldn't you have knocked? couldn't he have knocked? couldn't we have knocked? couldn't you have knocked? couldn't they have knocked?	couldn't I have been knocking? couldn't you have been knocking? couldn't he have been knocking? couldn't we have been knocking? couldn't you have been knocking? couldn't they have been knocking?