Also means
ah, right
Usage Note
ach so signals a sudden realisation or understanding, like oh, I see. It marks that new information has resolved a confusion: Ach so, das wusste ich nicht. Very frequent backchannel in dialogue.
Examples
"Ach so, du bist also schon umgezogen."
Natural Translation
Oh I see, so you've already moved.
Literal Translation
Ah so, you are thus already moved.
Related Words
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