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ah!; oh!; alas!
yes; indeed; that is correct
aah; gah; argh
hey!; yo!
uh huh; yeah yeah; right; gotcha
ああ、お腹が空いた。
Ah, I'm hungry.
ああ、久しぶりに会えて嬉しい。
Ah, I'm glad to see you after so long.
ああ、あんなに頑張ったのに残念だったね。
Ah, it's a shame after trying so hard.