English verb conjugation
SHOULD ALTER

Regular verb: alter - altered - altered

Affirmation

Simple form	V-ing form
I'd alter you'd alter he'd alter we'd alter you'd alter they'd alter	I'd be altering you'd be altering he'd be altering we'd be altering you'd be altering they'd be altering
Perfect	V-ing perfect
I should've altered you should've altered he should've altered we should've altered you should've altered they should've altered	I should've been altering you should've been altering he should've been altering we should've been altering you should've been altering they should've been altering

Negation

Simple form	V-ing form
I shouldn't alter you shouldn't alter he shouldn't alter we shouldn't alter you shouldn't alter they shouldn't alter	I shouldn't be altering you shouldn't be altering he shouldn't be altering we shouldn't be altering you shouldn't be altering they shouldn't be altering
Perfect	V-ing perfect
I shouldn't have altered you shouldn't have altered he shouldn't have altered we shouldn't have altered you shouldn't have altered they shouldn't have altered	I shouldn't have been altering you shouldn't have been altering he shouldn't have been altering we shouldn't have been altering you shouldn't have been altering they shouldn't have been altering

Interrogative form

Simple form	V-ing form
should I alter? should you alter? should he alter? should we alter? should you alter? should they alter?	should I be altering? should you be altering? should he be altering? should we be altering? should you be altering? should they be altering?
Perfect	V-ing perfect
should I have altered? should you have altered? should he have altered? should we have altered? should you have altered? should they have altered?	should I have been altering? should you have been altering? should he have been altering? should we have been altering? should you have been altering? should they have been altering?

Interro-negative form

Simple form	V-ing form
shouldn't I alter? shouldn't you alter? shouldn't he alter? shouldn't we alter? shouldn't you alter? shouldn't they alter?	shouldn't I be altering? shouldn't you be altering? shouldn't he be altering? shouldn't we be altering? shouldn't you be altering? shouldn't they be altering?
Perfect	V-ing perfect
shouldn't I have altered? shouldn't you have altered? shouldn't he have altered? shouldn't we have altered? shouldn't you have altered? shouldn't they have altered?	shouldn't I have been altering? shouldn't you have been altering? shouldn't he have been altering? shouldn't we have been altering? shouldn't you have been altering? shouldn't they have been altering?