The many jobs of "ne"

Introduction

呢 (ne) is a small sound at the end of a sentence that does several different jobs. The one to learn first is the cheapest question in Chinese: 我很好，你呢？(Wǒ hěn hǎo, nǐ ne?) — I'm fine, and you? One syllable carries the whole question the other person just asked.

Overview

Structure: Noun + 呢 (ne) ? ／ [Statement] + 呢 (ne)

Pattern	Example	Translation
N + 呢（bounce it back）	我很好，你呢？(Wǒ hěn hǎo, nǐ ne?)	I'm fine, and you?
N + 呢（where is it?）	我的书呢？(Wǒ de shū ne?)	Where's my book?
Question word + 呢	你为什么不去呢？(Nǐ wèishénme bú qù ne?)	Why aren't you going, then?
在 + V + 呢	他在睡觉呢。(Tā zài shuìjiào ne.)	He's asleep.
还 + V + 呢	他还在工作呢。(Tā hái zài gōngzuò ne.)	He's still working.

呢 (ne) is not 吗 (ma):

你好吗？(Nǐ hǎo ma?) — Are you well? A complete question on its own.

你呢？(Nǐ ne?) — And you? Only makes sense after something has been said.

呢 (ne) leans on the context. With no context, 我的书呢？(Wǒ de shū ne?) can only mean "where is my book?"

After a question word, 呢 (ne) softens rather than asks: 你为什么不去呢？(Nǐ wèishénme bú qù ne?) is gentler than the same sentence without it.

Examples

我很好，你呢？
Wǒ hěn hǎo, nǐ ne?
I'm fine, and you?
我的手机呢？
Wǒ de shǒujī ne?
Where's my phone?
他在睡觉呢，别打电话。
Tā zài shuìjiào ne, bié dǎ diànhuà.
He's asleep, don't ring.
你为什么不去呢？
Nǐ wèishénme bú qù ne?
So why aren't you going?
我吃中国菜，你呢？
Wǒ chī Zhōngguó cài, nǐ ne?
I'm having Chinese food; what about you?
他还在工作呢。
Tā hái zài gōngzuò ne.
He's still at work.

Usage Notes

呢 (ne) is neutral tone and always sits at the very end of the sentence.
Never pair it with 吗 (ma): ❌ 你好吗呢？(Nǐ hǎo ma ne?) They do different jobs and cannot share a sentence.
N + 呢 (ne) asks "where is it?" only when nothing has been said to bounce back. With context it means "and what about N?" — the same two words, read from the conversation.
With 在 (zài) or 还在 (hái zài), 呢 (ne) simply makes the sentence sound more spoken: 他在吃饭呢。(Tā zài chī fàn ne.)
呢 (ne) cannot turn a statement into a yes-no question. For that you need 吗 (ma) or 吧 (ba).