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How to Say ‘Be good.’ in Japanese

いい子にして。

ii ko ni shi te

[ee koh nee shee teh]

💬 Usage Tip: [いい子にして。] literally means “make yourself a good child,” but naturally it means “be good” or “behave.”

🇯🇵 In Japan: Parents say this to children very often, especially before leaving them somewhere or asking them to wait nicely.

Phrase Breakdown

いい子

ii ko

good child; well-behaved child

Refers to someone, especially a child, who is behaving well.

Example

いい子で待っていてね。

Wait here and be good.

Words in this phrase

いい

ii

[ee]

good

いい means “good.” In this phrase, it describes 子 and implies well-behaved.

Example

いい子にして。

Be a good child.

ko

[koh]

child

子 means “child.” いい子 means a good or well-behaved child.

Example

この子はいい子です。

This child is a good child.

にして

ni shi te

be; make (someone/something)

From する in the te-form, used here in the pattern 〜にして meaning 'behave as a good child' or 'be good.'

Example

いい子にしてね。

Be a good child, okay?

Words in this phrase

ni

[nee]

into; as

に marks the state to become. Here it means “into” or “as” in “be a good child.”

Example

いい子にしてまっていて。

Be a good child and wait.

shi

[shee]

do; make

し comes from する and means “do” or “make.” Here it helps form “make yourself/be.”

Example

ちゃんといい子にして。

Be a good child properly.

te

[teh]

do it; please

て-form here makes the phrase a request: “please be ...” or “stay ...”

Example

おるすばんのあいだ、いい子にして。

Be a good child while I'm out.

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