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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.
失って初めて気づく。
Only after losing it do you realize.
初めて料理を作ったときは大変だった。
It was hard when I cooked for the first time.