"Ah" ? When I chatting with my friends in English, I often write "Ah". I mean.. maybe, "Oh" or "I know" or "I see". "Ah" is similar to Japanese. So I often write and say it. It means "I know" or "I understand (what you mean, your feeling) in Japanese."あ～" like this. But.. my friends don't write so often. What does it mean "Ah"..? I made a mistake?