English verb conjugation
COULD POLISH

Regular verb: polish - polished - polished

Affirmation

Simple form	V-ing form
I could polish you could polish he could polish we could polish you could polish they could polish	I could be polishing you could be polishing he could be polishing we could be polishing you could be polishing they could be polishing
Perfect	V-ing perfect
I could have polished you could have polished he could have polished we could have polished you could have polished they could have polished	I could have been polishing you could have been polishing he could have been polishing we could have been polishing you could have been polishing they could have been polishing

Negation

Simple form	V-ing form
I couldn't polish you couldn't polish he couldn't polish we couldn't polish you couldn't polish they couldn't polish	I couldn't be polishing you couldn't be polishing he couldn't be polishing we couldn't be polishing you couldn't be polishing they couldn't be polishing
Perfect	V-ing perfect
I couldn't have polished you couldn't have polished he couldn't have polished we couldn't have polished you couldn't have polished they couldn't have polished	I couldn't have been polishing you couldn't have been polishing he couldn't have been polishing we couldn't have been polishing you couldn't have been polishing they couldn't have been polishing

Interrogative form

Simple form	V-ing form
could I polish? could you polish? could he polish? could we polish? could you polish? could they polish?	could I be polishing? could you be polishing? could he be polishing? could we be polishing? could you be polishing? could they be polishing?
Perfect	V-ing perfect
could I have polished? could you have polished? could he have polished? could we have polished? could you have polished? could they have polished?	could I have been polishing? could you have been polishing? could he have been polishing? could we have been polishing? could you have been polishing? could they have been polishing?

Interro-negative form

Simple form	V-ing form
couldn't I polish? couldn't you polish? couldn't he polish? couldn't we polish? couldn't you polish? couldn't they polish?	couldn't I be polishing? couldn't you be polishing? couldn't he be polishing? couldn't we be polishing? couldn't you be polishing? couldn't they be polishing?
Perfect	V-ing perfect
couldn't I have polished? couldn't you have polished? couldn't he have polished? couldn't we have polished? couldn't you have polished? couldn't they have polished?	couldn't I have been polishing? couldn't you have been polishing? couldn't he have been polishing? couldn't we have been polishing? couldn't you have been polishing? couldn't they have been polishing?