English verb conjugation
COULD DIMINISH

Regular verb: diminish - diminished - diminished

Affirmation

Simple form	V-ing form
I could diminish you could diminish he could diminish we could diminish you could diminish they could diminish	I could be diminishing you could be diminishing he could be diminishing we could be diminishing you could be diminishing they could be diminishing
Perfect	V-ing perfect
I could have diminished you could have diminished he could have diminished we could have diminished you could have diminished they could have diminished	I could have been diminishing you could have been diminishing he could have been diminishing we could have been diminishing you could have been diminishing they could have been diminishing

Negation

Simple form	V-ing form
I couldn't diminish you couldn't diminish he couldn't diminish we couldn't diminish you couldn't diminish they couldn't diminish	I couldn't be diminishing you couldn't be diminishing he couldn't be diminishing we couldn't be diminishing you couldn't be diminishing they couldn't be diminishing
Perfect	V-ing perfect
I couldn't have diminished you couldn't have diminished he couldn't have diminished we couldn't have diminished you couldn't have diminished they couldn't have diminished	I couldn't have been diminishing you couldn't have been diminishing he couldn't have been diminishing we couldn't have been diminishing you couldn't have been diminishing they couldn't have been diminishing

Interrogative form

Simple form	V-ing form
could I diminish? could you diminish? could he diminish? could we diminish? could you diminish? could they diminish?	could I be diminishing? could you be diminishing? could he be diminishing? could we be diminishing? could you be diminishing? could they be diminishing?
Perfect	V-ing perfect
could I have diminished? could you have diminished? could he have diminished? could we have diminished? could you have diminished? could they have diminished?	could I have been diminishing? could you have been diminishing? could he have been diminishing? could we have been diminishing? could you have been diminishing? could they have been diminishing?

Interro-negative form

Simple form	V-ing form
couldn't I diminish? couldn't you diminish? couldn't he diminish? couldn't we diminish? couldn't you diminish? couldn't they diminish?	couldn't I be diminishing? couldn't you be diminishing? couldn't he be diminishing? couldn't we be diminishing? couldn't you be diminishing? couldn't they be diminishing?
Perfect	V-ing perfect
couldn't I have diminished? couldn't you have diminished? couldn't he have diminished? couldn't we have diminished? couldn't you have diminished? couldn't they have diminished?	couldn't I have been diminishing? couldn't you have been diminishing? couldn't he have been diminishing? couldn't we have been diminishing? couldn't you have been diminishing? couldn't they have been diminishing?