-비가 왔거든.

It's raining. --> Because it was rainy?

=> Corrected : The sentence is corrected grammatically.

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-그래서 뭐했니? 집에 돌아왔니?

So what did you do?Are you come back home? --> Then, what did you do? Did you go back home?

=> Corrected : The sentence is corrected grammatically.

​

-응, 그랬어.

Yes, I did. ✔

​