English verb conjugation
COULD PREALTER

Regular verb: prealter - prealtered - prealtered

Affirmation

Simple form	V-ing form
I could prealter you could prealter she could prealter we could prealter you could prealter they could prealter	I could be prealtering you could be prealtering she could be prealtering we could be prealtering you could be prealtering they could be prealtering
Perfect	V-ing perfect
I could have prealtered you could have prealtered she could have prealtered we could have prealtered you could have prealtered they could have prealtered	I could have been prealtering you could have been prealtering she could have been prealtering we could have been prealtering you could have been prealtering they could have been prealtering

Negation

Simple form	V-ing form
I couldn't prealter you couldn't prealter she couldn't prealter we couldn't prealter you couldn't prealter they couldn't prealter	I couldn't be prealtering you couldn't be prealtering she couldn't be prealtering we couldn't be prealtering you couldn't be prealtering they couldn't be prealtering
Perfect	V-ing perfect
I couldn't have prealtered you couldn't have prealtered she couldn't have prealtered we couldn't have prealtered you couldn't have prealtered they couldn't have prealtered	I couldn't have been prealtering you couldn't have been prealtering she couldn't have been prealtering we couldn't have been prealtering you couldn't have been prealtering they couldn't have been prealtering

Interrogative form

Simple form	V-ing form
could I prealter? could you prealter? could she prealter? could we prealter? could you prealter? could they prealter?	could I be prealtering? could you be prealtering? could she be prealtering? could we be prealtering? could you be prealtering? could they be prealtering?
Perfect	V-ing perfect
could I have prealtered? could you have prealtered? could she have prealtered? could we have prealtered? could you have prealtered? could they have prealtered?	could I have been prealtering? could you have been prealtering? could she have been prealtering? could we have been prealtering? could you have been prealtering? could they have been prealtering?

Interro-negative form

Simple form	V-ing form
couldn't I prealter? couldn't you prealter? couldn't she prealter? couldn't we prealter? couldn't you prealter? couldn't they prealter?	couldn't I be prealtering? couldn't you be prealtering? couldn't she be prealtering? couldn't we be prealtering? couldn't you be prealtering? couldn't they be prealtering?
Perfect	V-ing perfect
couldn't I have prealtered? couldn't you have prealtered? couldn't she have prealtered? couldn't we have prealtered? couldn't you have prealtered? couldn't they have prealtered?	couldn't I have been prealtering? couldn't you have been prealtering? couldn't she have been prealtering? couldn't we have been prealtering? couldn't you have been prealtering? couldn't they have been prealtering?