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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
始めて猫を飼ったよ。
I got a cat for the first time.
日本に始めて来たのは去年です。
My first time coming to Japan was last year.
始めて雪を見たときは感動して写真をたくさん撮った。
When I saw snow for the first time, I was moved and took lots of photos.