should alter
Regular verb: alter - altered- altered

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I'd alter
you'd alter
she'd alter
we'd alter
you'd alter
they'd alter 	I'd be altering
you'd be altering
she'd be altering
we'd be altering
you'd be altering
they'd be altering	I should've altered
you should've altered
she 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
she 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 	Perfect 	V-ing perfect 	
I shouldn't alter
you shouldn't alter
she 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
she shouldn't be altering
we shouldn't be altering
you shouldn't be altering
they shouldn't be altering	I shouldn't have altered
you shouldn't have altered
she 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
she 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 	Perfect 	V-ing perfect 	
should I alter?
should you alter?
should she alter?
should we alter?
should you alter?
should they alter? 	should I be altering?
should you be altering?
should she be altering?
should we be altering?
should you be altering?
should they be altering? 	should I have altered?
should you have altered?
should she 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 she 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 	Perfect 	V-ing perfect 	
shouldn't I alter?
shouldn't you alter?
shouldn't she 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 she be altering?
shouldn't we be altering?
shouldn't you be altering?
shouldn't they be altering? 	shouldn't I have altered?
shouldn't you have altered?
shouldn't she 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 she have been altering?
shouldn't we have been altering?
shouldn't you have been altering?
shouldn't they have been altering?