YOU SAID:

Oh, hello! how much time you are here?

INTO JAPANESE

あ、こんにちは！あなたはここにどのくらいの時間ですか？

BACK INTO ENGLISH

Oh, hello! How long have you been here?

INTO JAPANESE

あ、こんにちは！ここには、どのくらいの期間いますか？

BACK INTO ENGLISH

Oh, hello! How long have you been here?