The type that would finish their summer homework by mid-July.
My workplace senior is an overachiever, who as a kid would probably finish their summer homework by mid-July.
I am the opposite. I would procrastinate in finishing my summer homework by late August
ご質問ありがとうございます。
この文脈で、[職場の先輩](https://eikaiwa.dmm.com/uknow/questions/117236/)について、「子供時代、夏休みの宿題をいつも7月中にすべて終わらせてたというタイプの人です」と言いたいなら、「My workplace senior is that type of person who as a kid would probably finish their summer homework by mid-July.」になります。
別の自然な言い方で「overachiever」と言えます。大きな成功を収める人とをさします。少し、揶揄い感じです。
My workplace senior is an overachiever, who as a kid would probably finish their summer homework by mid-July.
ちなみに「わたしは8月の終わりにいつも慌ててたひとです」と言いたいなら、「I am the opposite. I would procrastinate in finishing my summer homework by late August.」になります。
ご参考になれば幸いです。
the type of person who would finish all her summer homework before the end of July
この場合、次のような言い方ができますよ。
ーI know a lady from work who is the type of person who would finish all her summer homework before the end of July when she was in high school.
「職場の人で高校の時、夏休みの宿題を7月中に終わらせるタイプの人がいます」
the type of person who would finish all her summer homework before the end of July「7月中に夏休みの宿題を全て終わらせるタイプの人」
ーOn the other hand, I never finished all my summer homework until the end of August.
「その一方で、私は夏休みの宿題を8月末までに終わらせたことがなかった」
ご参考まで！
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