Here are the words used to express ‘strong obligations’ in Mandarin, with sentences illustrating their use. All of these words can be translated with the English word ‘must.’
得 děi
明天你得早点儿起来。
明天你得早點兒起來。
Míngtiān nǐ děi zǎo diǎr qǐlái.
You have to get up earlier tomorrow morning.
必得 bìděi
你必得按时来上课。
你必得按時來上課。
Nǐ bìděi ànshí lái shàng kè.
You must come to class on time.
必须/必須 bìxū
去中国以前你必须申请签证。
去中國以前你必須申請簽証。
Qù Zhōngguó yǐqián nǐ bìxū shēnqǐng qiānzhèng.
Before you go to China, you must apply for a visa.
必得 bìděi and 必须/必須 bìxū are more formal and stronger than 得 děi. 必须/必須 bìxū is also used in legal pronouncements and in other formal spoken and written contexts.
经济合同用货币履行义务时，… 必须用人民币计算和支付。
經濟合同用貨幣履行義務時，… 必須用人民幣計算和支付。
Jīngjì hétóng yòng huòbì lǚxíng yìwù shí, … bìxū yòng rénmínbì jìsuàn hé zhīfù.
When economic contracts provide for the performance of obligations through money, … Rénminbi must be used for calculating and paying obligations.
Here are the words used in Mandarin to express the kind of ‘weak obligations’ associated with the English words ‘should’ and ‘ought to,’ with sentences illustrating their use. In Mandarin, these words are also used to express moral obligations such as the responsibilities of parents to children or children to parents, and social obligations involving the things that a good person should do.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.
应该/應該 yīnggāi
父母应该照顾他们的孩子。
父母應該照顧他們的孩子。
Fùmǔ yīnggāi zhàogù tāmen de háizi.
Parents should take care of their children.
应当/應當 yīngdāng
你有错误就应当改正。
你有錯誤就應當改正。
Nǐ yǒu cuòwù jiù yīngdāng gǎizhèng.
When you make a mistake, you should correct it.
该/該 gāi
我该去上班了。
我該去上班了。
Wǒ gāi qù shàngbān le.
I should go to work.
In legal documents, 应/應 yīng often means ‘shall.’
经济合同被确认无效后，当事人依据该合同所取得的财产，应返还给对方。
經濟合同被確認無效後，當事人依據該合同所取得的財產，應返還給對方。
Jīngjì hétóng bèi quèrèn wúxiào hòu, dāngshìrén yījù gāi hétong suǒ qǔ dé de cáichǎn, yīng fǎnhuán gěi duìfāng.
After an economic contract has been confirmed to be invalid, the parties shall return to each other any property that they have acquired pursuant to the contract.
应/應 yīng may occur in legal texts to specify moral, though non-legal obligations. The following is an excerpt from Section 1, Article 3, of the Child Welfare Law of Taiwan.
父母、养父母或监护人对其儿童应负保育之责任。
父母、養父母或監護人對其兒童應負保育之責任。
Fùmǔ, yǎng fùmǔ huò jiānhù rén duì qí értóng yīng fù bǎoyù zhī zérèn.
Parents, foster parents, or legal guardians should bear the responsibility of rearing the children in the household.
The Mandarin words used to indicate that an action need not be done are 不必 bù bì, 不用 bù yòng, 甭 béng, 不须/不須 bù xū, and 无须/無須 wú xū.
不必 bù bì
他们明天不必来上课。
他們明天不必來上課。
Tāmen míngtiān bù bì lái shàng kè.
They don’t have to come to class tomorrow.
不用 bù yòng
你不用谢我。谢她。
你不用謝我。謝她。
Nǐ bù yòng xiè wǒ. Xiè tā.
You don’t have to thank me. Thank her.
甭 béng is the contraction of 不用 bù yòng. It is used in informal speech.
我们都是自己人。甭那么客气。
我們都是自己人。甭那麼客氣。
Wǒmen dōu shì zìjǐ rén. Béng nàme kèqi.
We are all friends. You don’t have to be so polite.
不须/不須 bù xū
去中国以前不须打针。
去中國以前不須打針。
Qù Zhōngguó yǐqián bù xū dǎ zhēn.
Before going to China it is not necessary to get vaccinations.
无须/無須 wú xū
这件事无须告诉你父母。
這件事無須告訴你父母。
Zhè jiàn shì wú xū gàosu nǐ fùmǔ.
There is no need to tell your parents about this matter.
(As for this matter, there is no need to tell your parents.)
To ask if there is an obligation to do something, use a yes–no question. 吗/嗎 ma questions can be used with all obligation words.
我们得看那本书吗？
我們得看那本書嗎？
Wǒmen děi kàn nà běn shū ma?
Do we have to read that book?
应该/應該 yīnggāi and 应当/應當 yīngdāng can also occur in verb-not-verb questions.
我应该不应该给他道歉？
我應該不應該給他道歉？
Wǒ yīnggāi bù yīnggāi gěi tā dàoqiàn?
Do I have to apologize to him?
我应当不应当给他道歉？
我應當不應當給他道歉？
Wǒ yīngdāng bù yīngdāng gěi tā dàoqiàn?
Should I apologize to him?
得 děi, 必得 bìděi, and 必须/必須 bìxū cannot occur in verb-not-verb questions.
The words used to express strong prohibitions in Mandarin are 不许/不許 bù xǔ ‘must not,’ 不要 bù yào ‘don’t,’ and 別 bié ‘don’t.’
医院里不许抽烟。
醫院裏不許抽煙。
Yīyuàn lǐ bù xǔ chōu yān.
Smoking is not permitted in the hospital.
別開玩笑。
Bié kāi wánxiào.
Don’t joke. (Be serious.)
考试以前不要紧张。
考試以前不要緊張。
Kǎoshì yǐqián bù yào jǐnzhāng.
Before a test don’t be nervous.
►12.5
The Mandarin words used to indicate that an action should not be done are 不应该/應該 bù yīnggāi and 不应当/應當 bù yīngdāng.
你不应该/应当打人。
你不應該/應當打人。
Nǐ bù yīnggāi/yīngdāng dǎ rén.
You shouldn’t hit people.
不应该/應該 bù yīnggāi ‘should not’ and 不应当/應當 bù yīngdāng ‘should not’ sometimes carry negative expectations. Both of the following sentences can be used after the fact, when we have seen that the medicine had side effects, or that Zhang San is a bad person.
这个药不应该有副作用啊。
這個藥不應該有副作用啊。
Zhège yào bù yīnggāi yǒu fù zuòyòng a.
This drug is not supposed to have any side effects.
张三不应该是坏人啊。
張三不應該是壞人啊。
Zhāng Sān bù yīnggāi shì huài rén a.
Zhang San is not supposed to be a bad person.
Here are some commonly used expressions in formal written texts that indicate prohibited activities. They are always followed by a verb phrase.
| 禁止 | jìnzhǐ + verb phrase | prohibited from |
| 免 | miǎn + verb phrase | prohibited from |
| 勿 | wù + verb phrase | do not |
| 严禁/嚴禁/ | yánjìn + verb phrase | strictly prohibited from |
| 不准 | bù zhǔn + verb phrase | not permitted to |
Here are the texts of actual signs posted in Chinese cities indicating prohibited activities. They illustrate the use of formal written words for prohibitions.