Indicative
Present
I alter
you alter
he alters
we alter
you alter
they alter
Present continuous
I'm altering
you're altering
he's altering
we're altering
you're altering
they're altering
Preterite
I altered
you altered
he altered
we altered
you altered
they altered
Preterite continuous
I was altering
you were altering
he was altering
we were altering
you were altering
they were altering
Present perfect
I've altered
you've altered
he's altered
we've altered
you've altered
they've altered
Present perfect continuous
I've been altering
you've been altering
he's been altering
we've been altering
you've been altering
they've been altering
Pluperfect
I'd altered
you'd altered
he'd altered
we'd altered
you'd altered
they'd altered
Pluperfect continuous
I'd been altering
you'd been altering
he'd been altering
we'd been altering
you'd been altering
they'd been altering
Future
I'll alter
you'll alter
he'll alter
we'll alter
you'll alter
they'll alter
Future continuous
I'll be altering
you'll be altering
he'll be altering
we'll be altering
you'll be altering
they'll be altering
Future perfect
I'll have altered
you'll have altered
he'll have altered
we'll have altered
you'll have altered
they'll have altered
Future perfect continuous
I'll have been altering
you'll have been altering
he'll have been altering
we'll have been altering
you'll have been altering
they'll have been altering
Conditional
Present
I'd alter
you'd alter
he'd alter
we'd alter
you'd alter
they'd alter
Present continuous
I'd be altering
you'd be altering
he'd be altering
we'd be altering
you'd be altering
they'd be altering
Past
I'd have altered
you'd have altered
he'd have altered
we'd have altered
you'd have altered
they'd have altered
Past continuous
I'd have been altering
you'd have been altering
he'd have been altering
we'd have been altering
you'd have been altering
they'd have been altering
Imperative
Imperative
alter
Let's alter
alter
Infinitive
Infinitive
to alter
Participle
Present
altering
Past
altered