English verb conjugation
COULD ESTABLISH

Regular verb: establish - established - established

Affirmation

Simple form	V-ing form
I could establish you could establish he could establish we could establish you could establish they could establish	I could be establishing you could be establishing he could be establishing we could be establishing you could be establishing they could be establishing
Perfect	V-ing perfect
I could have established you could have established he could have established we could have established you could have established they could have established	I could have been establishing you could have been establishing he could have been establishing we could have been establishing you could have been establishing they could have been establishing

Negation

Simple form	V-ing form
I couldn't establish you couldn't establish he couldn't establish we couldn't establish you couldn't establish they couldn't establish	I couldn't be establishing you couldn't be establishing he couldn't be establishing we couldn't be establishing you couldn't be establishing they couldn't be establishing
Perfect	V-ing perfect
I couldn't have established you couldn't have established he couldn't have established we couldn't have established you couldn't have established they couldn't have established	I couldn't have been establishing you couldn't have been establishing he couldn't have been establishing we couldn't have been establishing you couldn't have been establishing they couldn't have been establishing

Interrogative form

Simple form	V-ing form
could I establish? could you establish? could he establish? could we establish? could you establish? could they establish?	could I be establishing? could you be establishing? could he be establishing? could we be establishing? could you be establishing? could they be establishing?
Perfect	V-ing perfect
could I have established? could you have established? could he have established? could we have established? could you have established? could they have established?	could I have been establishing? could you have been establishing? could he have been establishing? could we have been establishing? could you have been establishing? could they have been establishing?

Interro-negative form

Simple form	V-ing form
couldn't I establish? couldn't you establish? couldn't he establish? couldn't we establish? couldn't you establish? couldn't they establish?	couldn't I be establishing? couldn't you be establishing? couldn't he be establishing? couldn't we be establishing? couldn't you be establishing? couldn't they be establishing?
Perfect	V-ing perfect
couldn't I have established? couldn't you have established? couldn't he have established? couldn't we have established? couldn't you have established? couldn't they have established?	couldn't I have been establishing? couldn't you have been establishing? couldn't he have been establishing? couldn't we have been establishing? couldn't you have been establishing? couldn't they have been establishing?