形容詞 childish:

1. indicating a lack of maturity
   同義詞：infantile

1. They derided his efforts as childish.
   他們嘲笑他的做法很幼稚。
2. A stupid, disgraceful, or childish act or performance.
   傻事，兒戲，輕率之舉愚蠢的，丟臉的或孩子氣的行為或表現(xiàn)
3. The little girl spoke in a high childish voice.
   小女孩說(shuō)話時(shí)聲音尖尖的，帶著童音。

child.ish

adj.（形容詞）
Of, relating to, or suitable for a child or childhood:
童年的：兒童或童年的，與兒童或童年有關(guān)的或適合于兒童或童年的：
例句：
a high, childish voice; childish nightmares.
響亮的童聲；兒童做的惡夢(mèng)

Marked by or indicating a lack of maturity; puerile:
未成熟的：以未成熟為特征或顯得未成熟的；幼稚愚蠢的：
例句：
tired of your childish pranks.
厭倦了你幼稚的胡鬧

Not complicated; simple.
不復(fù)雜的；簡(jiǎn)單的
Affected mentally by old age; senile.
年老糊涂的：智力上因年老而受影響的；年老糊涂的

【引伸】
child.ishly
adv.（副詞）
child.ishness
n.（名詞）