Did you start to take an interest in Japan after you began teaching English at DMM?
Did you have any interest in Japan before you started working here?
この場合、次のような言い方ができますよ。
ーDid you start to take an interest in Japan after you began teaching English at DMM?
「あなたが日本に興味を持ち始めたのはDMMで英語を教え始めた後ですか？」
ーDid you have any interest in Japan before you started working here?
「日本で働き始める前に、日本に興味はありましたか？」
ご参考まで！
Were you interested in Japan before you started teaching at DMM?
Did you become interested in Japan after you started teaching at DMM?
Were you interested in Japan before you started teaching at DMM?
DMMで教え始める前から日本に興味があったのですか？
Did you become interested in Japan after you started teaching at DMM?
DMMで教え始めてから日本に興味を持ったのですか？
上記のように英語で表現することができます。
become interested は「興味を持つ」という意味の英語表現です。
お役に立てれば嬉しいです。
"Were you interested in Japan before you started teaching on DMM?"
- "Were you interested in Japan before you started teaching on DMM?"
"were you interested in Japan" 「あなたが日本の興味を持」"did you have an interest in Japan" も言えます。
"before ~" 「〜の前に」
"you started teaching on DMM" 「DMMで教えて始めて」
カナダ 
アメリカ合衆国 
オーストラリア 
