Could you tell us what you put your most effort into during your student years?
What was the one thing that you worked on the hardest during your time as a student?
ご質問ありがとうございます。
① "Could you tell us what you put your most effort into"＝「私たちにあなたが最も努力したものを教えてくれますか」
"during your student years?"＝「学生のときに？」
② "What was the one thing that you worked on the hardest"＝「あなたがもっとも努力したものは何ですか」
"during your time as a student?"＝「あなたが学生だったとき？」
ご参考までに。
アメリカ合衆国 
