YOU SAID:
He didn't understand that he was at the wrong house.
INTO JAPANESE
彼は自分が間違った家に居るのを理解していなかった。
BACK INTO ENGLISH
He didn't understand that he was in the wrong house.
INTO JAPANESE
彼は自分が間違った家に居るのを理解していなかった。
BACK INTO ENGLISH
He didn't understand that he was in the wrong house.
Well done, yes, well done!