English verb conjugation
COULD REFILTER

Regular verb: refilter - refiltered - refiltered

Affirmation

Simple form	V-ing form
I could refilter you could refilter he could refilter we could refilter you could refilter they could refilter	I could be refiltering you could be refiltering he could be refiltering we could be refiltering you could be refiltering they could be refiltering
Perfect	V-ing perfect
I could have refiltered you could have refiltered he could have refiltered we could have refiltered you could have refiltered they could have refiltered	I could have been refiltering you could have been refiltering he could have been refiltering we could have been refiltering you could have been refiltering they could have been refiltering

Negation

Simple form	V-ing form
I could not refilter you could not refilter he could not refilter we could not refilter you could not refilter they could not refilter	I could not be refiltering you could not be refiltering he could not be refiltering we could not be refiltering you could not be refiltering they could not be refiltering
Perfect	V-ing perfect
I could not have refiltered you could not have refiltered he could not have refiltered we could not have refiltered you could not have refiltered they could not have refiltered	I could not have been refiltering you could not have been refiltering he could not have been refiltering we could not have been refiltering you could not have been refiltering they could not have been refiltering

Interrogative form

Simple form	V-ing form
could I refilter? could you refilter? could he refilter? could we refilter? could you refilter? could they refilter?	could I be refiltering? could you be refiltering? could he be refiltering? could we be refiltering? could you be refiltering? could they be refiltering?
Perfect	V-ing perfect
could I have refiltered? could you have refiltered? could he have refiltered? could we have refiltered? could you have refiltered? could they have refiltered?	could I have been refiltering? could you have been refiltering? could he have been refiltering? could we have been refiltering? could you have been refiltering? could they have been refiltering?

Interro-negative form

Simple form	V-ing form
could I not refilter? could you not refilter? could he not refilter? could we not refilter? could you not refilter? could they not refilter?	could I not be refiltering? could you not be refiltering? could he not be refiltering? could we not be refiltering? could you not be refiltering? could they not be refiltering?
Perfect	V-ing perfect
could I not have refiltered? could you not have refiltered? could he not have refiltered? could we not have refiltered? could you not have refiltered? could they not have refiltered?	could I not have been refiltering? could you not have been refiltering? could he not have been refiltering? could we not have been refiltering? could you not have been refiltering? could they not have been refiltering?