朝气蓬勃 [- - pénɡ bó]full of youthful spirit; bubble over with life; full of vigour and vitality; imbued with vitality; vigorous and dynamic; fresh and vigorous; teem with life and vitality; the vigour of youth:
•¶朝气蓬勃的青年 spirited young people
•¶ 青年人朝气蓬勃， 好像早晨八、九点钟的太阳。 Young people are full of vigour and vitality, like the sun at eight or nine in the morning.