Modal verbs occur before a verb and express the meanings of possibility, ability, permission, obligation, and prohibition.
明天会下雨。
明天會下雨。
Míngtiān huì xià yǔ.
It may rain tomorrow.
我希望我们将来会有机会再见。
我希望我們將來會有機會再見。
Wǒ xīwàng wǒmen jiānglái huì yǒu jīhuì zài jiàn.
I hope that in the future we will have the chance to meet again.
Notice that this meaning of 会/會 huì also implies future time.
► 36.3
会/會 huì expresses innate ability or ability based on learning and knowledge. The negative is 不会/不會 bù huì.
她会说中文。
她會說中文。
Tā huì shuō Zhōngwén.
She can speak Chinese.
我不会写那个字。
我不會寫那個字。
Wǒ bù huì xiě nàge zì.
I can’t write that character.
能 néng expresses physical ability or the unobstructed ability to perform some action. 不能 bù néng is used when performance is obstructed.
你能不能把桌子搬到那边去？
你能不能把桌子搬到那邊去？
Nǐ néng bù néng bǎ zhuōzi bān dào nàbiān qù?
Can you move this table over there?
(lit. ‘Can you take this table and move it over there?’)
他的嗓子疼， 不能说话。
他的嗓子疼， 不能說話。
Tā de sǎngzi téng, bù néng shuō huà.
His throat is sore. He can’t speak.
现在在修路。 不能过。
現在在修路。 不能過。
Xiànzài zài xiū lù. Bù néng guò.
The road is being repaired now. You can’t cross it.
► 52.1.3
可以 kěyǐ is sometimes used to express knowledge-based or physical ability. The negative is 不可以 bù kěyǐ.
你可以不可以写你的名字？
你可以不可以寫你的名字？
Nǐ kěyǐ bù kěyǐ xiě nǐ de míngzi?
Can you write your name?
她已经八十岁了， 可是还可以骑自行车。
她已經八十歲了， 可是還可以騎自行車。
Tā yǐjing bāshí suì le, kěshì hái kěyǐ qí zìxíngchē.
She is already eighty years old but can still ride a bicycle.
The primary use of 可以 kěyǐ is to express permission to perform an action. The negative is 不可以 bù kěyǐ.
妈妈说我可以跟你去看电影。
媽媽說我可以跟你去看電影。
Māma shuō wǒ kěyǐ gēn nǐ qù kàn diànyǐng.
Mom said I can go with you to see a movie.
你才十六岁。 不可以喝酒。
你才十六歲。 不可以喝酒。
Nǐ cái shíliù suì. Bù kěyǐ hē jiǔ.
You are only 16 years old. You cannot drink alcohol.
► 51.2
Obligations may be strong (must) or weak (should). In Mandarin, as in English, negation often changes the force of the words used to express obligation. This section presents a brief overview of the use of modal verbs to express obligations. For more on expressing obligations, see Chapter 50.
The Mandarin words used to indicate strong obligation (must) are 必须/必須 bìxū, 必得 bìděi, and 得 děi. 必得 bìděi and 必须/必須 bìxū are more formal than 得 děi. 必须/必須 bìxū is used in legal pronouncements and in other formal spoken and written contexts.
必须/必須 bìxū
婚前必须做健康检查。
婚前必須做健康檢查。
Hūn qián bìxū zuò jiànkāng jiǎnchá.
Before you get married you must have a physical exam.
必得 bìděi
医生说我每天必得吃药。
醫生說我每天必得吃藥。
Yīshēng shuō wǒ měitiān bìděi chī yào.
The doctor says I must take medicine every day.
得 děi
住院以前得先付钱。
住院以前得先付錢。
Zhù yuàn yǐqián děi xiān fù qián.
Before being admitted to the hospital you must first pay a fee.
► 50.1.1
The modal verbs used to express weak obligations (should) associated with social or moral responsibilities include 应该/應該 yīnggāi, 该/該 gāi, 应当/應當 yīngdāng, and 当/當 dāng. 应当/應當 yīngdāng is more formal than 应该/應該 yīnggāi and can be used in formal texts including legal documents. 该/該 gāi is used in informal speech. 应/應 yīng is used in formal texts including legal documents. For illustrations of legal uses, see
► 50.1.2
应该/應該 yīnggāi
学生应该认真地学习。
學生應該認真地學習。
Xuésheng yīnggāi rènzhēn de xuéxí.
Students should study conscientiously.
该/該 gāi
你该早一点睡觉。
你該早一點睡覺。
Nǐ gāi zǎo yīdiǎn shuì jiào.
You should go to sleep a little earlier.
孩子应当尊敬父母。
孩子應當尊敬父母。
Háizi yīngdāng zūnjìng fùmǔ.
Children should respect their parents.
► 50.1.2
不必 bù bì expresses negative obligation, using the syllable 必 bì that occurs in the strong obligation modal verbs 必得 bìděi and 必须/必須 bìxū. For additional ways to express negative obligations, see 50.1.3.
你去看朋友的时候不必送礼物。
你去看朋友的時候不必送禮物。
Nǐ qù kàn péngyou de shíhou bù bì sòng lǐwù.
When you visit friends, it is not necessary to bring a gift.
The following phrases involving modal verbs are used to express prohibitions. For additional phrases used in expressing prohibitions, see
► 50.2
不可以 bù kěyǐ ‘not allowed to’
考试的时候不可以说话。
考試的時候不可以說話。
Kǎoshì de shíhou bù kěyǐ shuō huà.
During the test you cannot speak.
不能 bù néng ‘cannot’
这些书都是内部刊物。 你不能借。
這些書都是內部刊物。 你不能借。
Zhè xiē shū dōu shì nèi bù kānwù. Nǐ bù néng jiè.
Those books are all restricted publications. You can’t borrow them.
这件事情， 我不能告诉你。
這件事情， 我不能告訴你。
Zhè jiàn shìqing, wǒ bù néng gàosu nǐ.
(As for) this matter, I can’t tell you about it.
不许/不許 bù xǔ ‘must not, not allowed’
不许/不許 bù xǔ is used in formal speech and writing.
图书馆里不许抽烟、 吃东西。
圖書館裏不許抽煙、 吃東西。
Túshūguǎn lǐ bù xǔ chōu yān, chī dōngxi.
You are not allowed to smoke or eat (things) in the library.
► 50.2.1
Modal verbs are always negated with 不 bù and never with 没/沒 méi.
| Say this | Not this |
| 他不会说中文。 | *他没会说中文。 |
| 他不會說中文。 | 他沒會說中文。 |
| Tā bù huì shuō Zhōngwén. | Tā méi huì shuō Zhōngwén. |
| He can’t speak Chinese. | |
| 你不应该抽烟。 | *你没应该抽烟。 |
| 你不應該抽煙。 | 你沒應該抽煙。 |
| Nǐ bù yīnggāi chōu yān. | Nǐ méi yīnggāi chōu yān. |
| You shouldn’t smoke. |
Modal verbs indicating weak obligation, 会/會 huì, 可以 kěyǐ, 能 néng, 应该/應該 yīnggāi, and 应当/應當 yīngdāng, have the properties of stative verbs.
► 11
Modal verbs can serve as the verb in verb-not-verb questions, and they can be used as the short, one word answers to yes–no questions.
| Question | Response |
| 你会不会说中文？ | 会。 |
| 你會不會說中文？ | 會。 |
| Nǐ huì bù huì shuō Zhōngwén? | Huì. |
| Can you speak Chinese? | (I) can. |
| 我可以不可以借你的车？ | 可以。 |
| 我可以不可以借你的車？ | |
| Wǒ kěyǐ bù kěyǐ jiè nǐ de chē? | Kěyǐ. |
| Can I borrow your car? | (You) can. |
| 你能不能帮助我？ | 能。 |
| 你能不能幫助我？ | |
| Nǐ néng bù néng bāngzhù wǒ? | Néng. |
| Can you help me? | (I) can. |
| 我们该不该交作业？ | 该。 |
| 我們該不該交作業？ | 該。 |
| Wǒmen gāi bù gāi jiāo zuòyè? | Gāi. |
| Should we hand in our homework? | (We) should. |
► 28
会/會 huì and 能 néng can be modified by intensifiers.
那个人很会跳舞。
那個人很會跳舞。
Nàge rén hěn huì tiào wǔ.
That person can really dance.
中國人很能吃苦。
Zhōngguórén hěn néng chī kǔ.
Chinese people can endure a lot of hardship.
For a complete list of intensifiers, see 10.3.
会/會 huì, 能 néng, and 可以 kěyǐ can be used in the structures 越来越 yuè lái yuè and 越 verb 越 verb yuè verb yuè verb to indicate change over time.
他越来越会说话。
他越來越會說話。
Tā yuè lái yuè huì shuō huà.
He is becoming more and more elegant (diplomatic) in his speech.
他越来越能适应英国的生活了。
他越來越能適應英國的生活了。
Tā yuè lái yuè néng shìyìng Yīngguó de shēnghuó le.
Little by little he is getting used to British life.
我越来越可以适应这种天气了。
我越來越可以適應這種天氣了。
Wǒ yuè lái yuè kěyǐ shìyìng zhè zhǒng tiānqì le.
Little by little, I’ve become able to cope with this kind of weather.
► 38.3
The modal verbs that indicate strong obligation, 必须/必須 bìxū, 必得 bìděi, and 得 děi, are similar to adverbs.
They cannot serve as the verb in verb-not-verb questions.
| Say this | Not this |
| 你必须马上回家吗？ | *你必须不必须马上回家？ |
| 你必須馬上回家嗎？ | 你必須不必須馬上回家？ |
| Nǐ bìxū mǎshàng huí jiā ma? | Nǐ bìxū bù bìxū mǎshàng huí jiā? |
| Do you have to go right home? | |
| 我们得在这儿注册吗？ | *我们得不得在这儿注册？ |
| 我們得在這兒註冊嗎？ | 我們得不得在這兒註冊？ |
| Wǒmen děi zài zhèr zhù cè ma? | Wǒmen děi bù děi zài zhèr zhù cè? |
| Do we have to register here? |
The modal 得 děi cannot be used as the one-word answer to yes-no questions:
| Question | Respond with this | Not this |
| 今天得注册吗？ | 今天得注册。 | *得。 |
| 今天得註冊嗎？ | 今天得註冊。 | |
| Jīntiān děi zhù cè ma? | Jīntiān děi zhù cè. | Děi |
| Do we have to register today? | We have to register today. or 对。/ 對。 Duì. Correct. |