そういえば (souieba)

そういえば、早くお金返してよ。

That reminds me, give me my money back. // That reminds me, hurry up and pay back the money you owe me.

そういえば美咲ってスイーツ好きだよね？

Now that you mention it, Misaki likes sweets, doesn't she? // Come to think of it, you (=Misaki) like sweets, right?

"そう言えば、ずっと変な夢を見てたような気がするんだけど...別の人の人生の夢？"

Hmm, I feel like I've just been in a weird dream for a long time… Like I was in someone else's life?