YOU SAID:
"What is the reason you want to become an English teacher?"
INTO JAPANESE
「英語教師になりたい理由は何ですか?」
BACK INTO ENGLISH
"Why do you want to be an English teacher?"
INTO JAPANESE
「なぜ英語の先生になりたいのですか?」
BACK INTO ENGLISH
"Why do you want to be an English teacher?"
That didn't even make that much sense in English.