That person taught me the importance of being persistent in all that I set out to do.
質問ありがとうございます。
”何事も粘り強く取り組むことが大事だとその人は教えてくれた” = ”That person taught me the importance of being persistent in all that I set out to do."
何事も=Everything/All
粘り強く=To be persistent
取り組む=To set out to do/To work on
大事=Important
その人は教えてくれた=That person taught me
また質問をお待ちしています!