English verb conjugation
COULD MATTER

Regular verb: matter - mattered - mattered

Affirmation

Simple form	V-ing form
I could matter you could matter he could matter we could matter you could matter they could matter	I could be mattering you could be mattering he could be mattering we could be mattering you could be mattering they could be mattering
Perfect	V-ing perfect
I could have mattered you could have mattered he could have mattered we could have mattered you could have mattered they could have mattered	I could have been mattering you could have been mattering he could have been mattering we could have been mattering you could have been mattering they could have been mattering

Negation

Simple form	V-ing form
I could not matter you could not matter he could not matter we could not matter you could not matter they could not matter	I could not be mattering you could not be mattering he could not be mattering we could not be mattering you could not be mattering they could not be mattering
Perfect	V-ing perfect
I could not have mattered you could not have mattered he could not have mattered we could not have mattered you could not have mattered they could not have mattered	I could not have been mattering you could not have been mattering he could not have been mattering we could not have been mattering you could not have been mattering they could not have been mattering

Interrogative form

Simple form	V-ing form
could I matter? could you matter? could he matter? could we matter? could you matter? could they matter?	could I be mattering? could you be mattering? could he be mattering? could we be mattering? could you be mattering? could they be mattering?
Perfect	V-ing perfect
could I have mattered? could you have mattered? could he have mattered? could we have mattered? could you have mattered? could they have mattered?	could I have been mattering? could you have been mattering? could he have been mattering? could we have been mattering? could you have been mattering? could they have been mattering?

Interro-negative form

Simple form	V-ing form
could I not matter? could you not matter? could he not matter? could we not matter? could you not matter? could they not matter?	could I not be mattering? could you not be mattering? could he not be mattering? could we not be mattering? could you not be mattering? could they not be mattering?
Perfect	V-ing perfect
could I not have mattered? could you not have mattered? could he not have mattered? could we not have mattered? could you not have mattered? could they not have mattered?	could I not have been mattering? could you not have been mattering? could he not have been mattering? could we not have been mattering? could you not have been mattering? could they not have been mattering?