啊
ā
interjection of surprise, Ah!, Oh!
à
interjection or grunt of agreement, uhm, Ah, OK, expression of recognition, Oh, it's you!
á
interjection expressing doubt or requiring answer, Eh?, what?
ǎ
interjection of surprise or doubt, Eh?, My!, what's up?
a
modal particle ending sentence, showing affirmation, approval, or consent