flower 花 ；花朵，youth 青春 ; 年轻 ; 青年时期，in the flower of sb's youth 风华正茂之时

【例句】
Mark dropped out of college in theflower of his youth.
马克在风华正茂之时从大学中途退学。

Look at those students – they're all in the flower of their youth.
看看那些学生，他们正处于风华正茂之时。