n.青年，少壮; 青春

My Youthfulness → 我的青春谁做主；我国青春；我的青春
youthfulness detail → 青春
Youthfulness of spirit → 年轻的心灵
Youthfulness from Rajasthan → 拉贾斯坦焕肤排毒护理

1.It is the Foundation of Youthfulness.
[汉]那是年轻的秘诀。
2.But of course we're actually about extending or restoring physical and mental youthfulness and vitality.
[汉]但是，我们当然实际上是扩展和保持体力的和精神的年轻和活力。

【Noun】

1. the freshness and vitality characteristic of a young person