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for the first time
only after ... is it ...; only when ... do you ...; not until ... do you ...
first time; (one's) first
日本に初めて来ました。
I came to Japan for the first time.
初めて料理を作ったときは失敗した。
I failed when I cooked for the first time.
この歳になって初めて気づくことも多いなあ。
There are many things I realize for the first time at this age.