Comparing "hui," "neng," "keyi"

This is one of the trickiest comparisons, as 会 (huì), 能 (néng), and 可以 (kěyǐ) are often translated as "can." Sometimes they are explained as: 会 means "know how to", 能 means "to be able to", and 可以 means "to have permission to." Actually, they overlap a little bit. To visualize the differences and similarities please refer to Chinese Modal Verb Venn Diagram.

Basic Meanings

The words 会 (huì), 能 (néng), and 可以 (kěyǐ) actually overlap a little in meaning. The first step is to understand their basic meanings, though:

1. 会 (huì) can mean "know how to" and can express an action that you had to learn or be trained in to do.
2. 能 (néng) means "to be able to" and expresses having a certain ability or having obtained a certain minimum requirement.
3. 可以 (kěyǐ) means "may" or "to be allowed to" and expresses having another person's permission.

Expressing Ability

Both 会 and 能 can be used to express ability in something.

Structure

会/能 + Verb

Examples

• 他 会 修 电脑。 He knows how to fix computers.
• 我 会 跳舞。 I know how to dance.
• 我 学 了 两 年 才 会 说 一点 汉语。 I studied for two years before I knew how to speak a little Chinese.

• 你 真的 能 吃 三 碗 米饭 吗？ Are you really able to eat three bowls of rice?
• 你 能 记 住 所有 国家 的 名字 吗？ Are you able to remember the names of all countries?
• 三 个 月 的 小 孩子 不 能 走路。 Three month old children are unable to walk.

Expressing Permission

可以 is used to ask for or give permission. However, 能 can also be used to replace 可以 interchangeably.

Structure

可以/能 + Verb

Examples

• 我 可以/能 进来 吗？ Am I allowed to enter?
• 你 可以/能 帮 我 一下 吗？ Could you help me a bit?
• 不 可以/能 带 危险 物品 上车。 You're not allowed to bring dangerous things in the car.

Talking about the Future

Only 会 can be used to mean something is going to happen. It express something in the future will happen and is often used to express trends or possibilities.

Structure

会 + Verb

Examples

• 明天 你 会 来 吗？ Will you come tomorrow?
• 你 太 过分 了，没 有 人 会 这么 做。 You're too excessive, no one will do it like this.
• 一会儿 会 下雨 吗？ Will it rain in a minute?

Adding 很 to create emphasis

By placing the character 很 (hěn) before 会, it adds emphasis to the level of ability and skill on the action present. 很会 is commonly used to mean 'to be good at" and expresses being very skillful at something, or doing something very well. It can be translated as "really can", as in "you really can speak Chinese!", in other words, "you are good at speaking Chinese."

When 很 is placed in front of 能, the meaning takes on a amazed/surprised tone on the action. Although more rarely used, it emphasis quantity and amount. 很能 is most commonly used with 吃(chī) to eat, and 睡 (shuì) to sleep. It's like the English equivalent of saying you "can really" do something. For example saying that someone "can really sleep" means that they can sleep a lot.

Note: 很可以 is not a phrase and therefore can not be used with 会 to add emphasis.

Structure

很会/很能 + Verb

Examples

• 这 个 女 孩子 很 会 唱歌。 This girl can sing really well.
• 我 的 妈妈 很 会 做 饭。 The mom cooks very well. My mother really knows how to cook.
• 他 很 会 骗 人。 He can really deceive people.
• 你 很会 打 羽毛球，以后 应该 当 个 专业 羽毛球 运动员。 You can really play badminton well, you should be a professional badminton player when you grow up.

• 你 很 能 吃 吗！ The subject can eat a lot. Wow, you really can eat!
• 你 很 能 睡。 The subject can sleep a lot, for many hours. You can really sleep.
• 他 今天 会 这么 成功 是 因为 他 是 一个 很能 吃苦 的 人。 The reason he is so successful today is because he is a person who can handle a lot of burdens.

• 他很会说话。
The subject has great skill in speaking, he speaks well with high level terms/sentence structure. He really knows how to talk.
• 他很能说话。
The subjects talks a lot. He can really talk.
• 他很可以说话。

• 她很会吃。
The subject has great knowledge about food and its culture, a true connoisseur. She really knows how to eat.
• 她很能吃。
The subjects eats a lot, a great amount. </expl> She can really eat.
• 她很可以吃。

Examples of similar expressions, but with different meanings

• 我 现在 能 跳舞 了，我 的 脚 伤 好 了。 I am able to dance now, my foot is better. (The condition changed)
• 我 现在 会 跳舞 了，我 学 了 两 个 月。 I know how to dance now, I studied for two months. (It's a learned skill)
• 我 现在 可以 跳舞 了，我 爸爸 同意 了。 I'm allowed to dance now, my dad agreed. (The dad gave permission)

• 我 们 学 了 半 年 中文，现在 我会说 一 点 中 文。 We have learned half a year of Chinese, now I know how to speak a little bit of Chinese (The speaker now knows a new language)
• 你 能 用 中文 演讲 吗？ Can you use Chinese to make a speech? (The speaker is asking if that person has the ability to)
• 我 们 已 经 说 了 两 个 小 时 英文，现在 可 以 说 中文 吗？ We have already spoken two hours of English, can we speak Chinese now? (The speaker is asking for permission)

• 我 会 做 中国 菜。 I know how to make Chinese food.
• 你 能 吃 辣 的 中国 菜 吗？Can you eat (do you have the ability to) eat spicy Chinese food?
• 我 们 可以 去 吃中国 菜 吗？Can we go eat Chinese food? (Asking for permission)

Similarities

会， 能， 可以 share a few essential rules. The first common rule shared by these three is that none of them can be followed by an aspectual particle.

• 他会做饭。
He knows how to eat.
• 他会过做饭。

Secondly, 会, 能, and 可以 have to come before any prepositional phrases or descriptive adverbial modifiers in the sentence.

• 你可以把课本再看一次，看完以后再来考试。You can read over the textbook again, when you're done come back to take the test.
• 你把课本可以再看一次， 看完以后再来考试。
• 他们会努力地读一读。They will seriously read it over.
• 他们努力地会读一读。

Example dialog

• A: 我 可以 和 他们 一起 踢 足球 吗？ Can I play soccer with them? (Am I allowed?)
• B: 你 的 腿 还 没 好，现在 你 不 能 踢。 Your foot still isn't better. You can't go right now. (His rule prohibits it)
• A: 它 会 好 吗？ Will it get better? (会 indicates the future)
• B: 嗯，你 放 心 吧，很 快 就 会 好 的。 Yes, don't worry, it will get better soon.

For a good visualization on how these three overlap, check out the Chinese Modal Verb Venn Diagram.

See also

• Auxiliary verb "hui" for "will"
• Expressing a learned skill
• Expressing ability or possibility
• Expressing permission

Sources and further reading

Books

• 对外汉语教学语法释疑201例 (p.55,p.65) →buy
• Integrated Chinese: Level 1, Part 1 (3rd ed) (pp. 219-20) →buy

Dictionaries

• 现代汉语词典（第5版） (能p.989， 可以p.773，会p.610) →buy

Websites

• sinosplice: http://www.sinosplice.com/life/archives/2009/10/13/chinese-modal-verb-venn-diagram