Correct

稚嫩

/ zhìnèn / 
Strokes

Definition

young and tender/puerile/soft and immature

Example

As an Adjective

young and tender

1
Zhìnèn
稚嫩
de
的
xīnlíng
心灵

innocent heart (of a child)

2
Zhìnèn
稚嫩
de
的
tóngyīn
童音

child's tender voice

As an Adjective

immature

3
Chūxué
初学
xiězuò
写作
  
,
wénbǐ
文笔
nánmiǎn
难免
zhìnèn
稚嫩
  
。

Immaturity is unavoidable in beginner's writing.