young at heart
US /jʌŋ æt hɑːrt/
UK /jʌŋ æt hɑːrt/

1.
心态年轻, 心境年轻
having a youthful spirit and attitude, regardless of one's actual age
:
•
My grandmother is 80, but she's still young at heart and loves to dance.
我奶奶80岁了,但她仍然心态年轻,喜欢跳舞。
•
He's always up for an adventure, truly young at heart.
他总是乐于冒险,真是心态年轻。