jīng / guò / duō / nián / de / nǔ / lì / ， / tā / zhōng / yú / rù / liú / ， / huò / dé / le / cān / jiā / zhèng / shì / bǐ / sài / de / zī / gé / 。

经过多年的努力，他终于入流，获得了参加正式比赛的资格。

After years of hard work, he finally became qualified to take part in official competitions.