In the manner of a young person; youthfully; immaturely.

= youthfully, adv.

In a youthful manner; with the freshness, vigour, or other characteristic of youth; like a young person; in a juvenile style.

(a) adj. resembling or having the character of youth, juvenile (cf. youthly, adj.); (b) adv. like a youth, or in the manner of youth.

in a puerile fashion; childishly.

In a green or verdant manner; freshly, flourishingly.

with the appearance of youth.

in a juvenile or youthful way.