I see what you mean now that you mention it, but I wouldn't have picked up on it by myself.
I get it now that you have explained it to me, but I wouldn't have thought of that by myself.
ーI see what you mean now that you mention it, but I wouldn't have picked up on it by myself.
「言われてみればそうだけど、気がつかなかった」
I see what you mean now that you mention it で「あなたがそれに言及してあなたの意味することがわかった」
I wouldn't have picked up on it by myself. で「自分自身では気がつかなかっただろう」
ーI get it now that you have explained it to me, but I wouldn't have thought of that by myself.
「言われてみればそうだけど、気がつかなかった」
I get it now that you have explained it to me で「あなたが私に説明してくれてわかった」
I wouldn't have thought of that by myself. で「自分ではそれを思いつかなかっただろう」
ご参考まで！
**例文:**
- *"Now that you mention it, I see what you mean."*
**（言われてみれば、確かにそうだね。）**
- *"I hadn't realized that until you brought it up."*
**（あなたが話すまで、全然気づかなかったよ。）**
- *"That's a good observation! I never noticed that before."*
**（いい指摘だね！今まで気づかなかったよ。）**
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**関連単語・表現:**
- **Realize**（気づく、認識する）
- **Notice**（気づく、発見する）
- **Point out**（指摘する）
- **Bring up**（話題に出す）
- **Good point**（いい指摘）
---
Now that you mention it, you're right, but I didn't notice it at all.
Come to think of it（そう言えば、考えてみれば）や Now that you mention it という決まり文句を使うのが自然です。これに、気づかなかったことを表す I didn't notice や I didn't realize を組み合わせることで、きれいにニュアンスを表現できます。
例えば下記のように表現できます。
・Now that you mention it, you're right, but I didn't notice it at all.
『言われてみればそうだけど、全然気づかなかったよ。』
・I didn't realize that until you mentioned it.
『あなたに言われるまで、そのことに気づかなかったよ。』
カナダ 
アメリカ合衆国 
