How do I know if 得 is pronounced děi or de?

If the word means 'must' or 'have to' and is followed by a verb, it is pronounced děi (third tone). If it appears between a verb and a complement describing the action (e.g., 跑得很快), it is the particle de (neutral tone). Context and grammar always indicate the correct pronunciation.

When do I use 得 (děi) vs 得 (de)?

Use 得 (děi) to express obligation or necessity (like 'must' in English). Use 得 (de) as a structural particle to link a verb to a complement of degree or result. They are completely different in function and pronunciation, so you cannot substitute one for the other.

How do I negate a sentence with 得 (děi) and with 得 (de)?

To negate 得 (děi), use 不用 (bùyòng) before the verb (e.g., 你不用去 'You don't have to go'). To negate a complement with 得 (de), put 不 after 得 (e.g., 他跑得不快 'He doesn't run fast'). Do not use 不 before 得 in either case.

Can I use 得 (de) in potential complements like 跑得快?

The potential complement construction (Verb + 得 + Result, e.g., 跑得快 'can run fast') uses a different grammatical 得 (same character, but often considered a separate usage). Its negation is Verb + 不 + Result (e.g., 跑不快). This is not the same as the degree complement marker discussed here. Do not mix the negation patterns – for degree complements, always use 得不.

Easily confusedHSK 3

得 (děi) vs 得 (de): modal 'must' vs complement marker

The character 得 has two distinct uses: as a modal verb pronounced děi, meaning 'must' or 'have to', and as a grammatical particle pronounced de, used after verbs to link a complement of degree or result. They are not interchangeable; context determines the pronunciation and function.

In Chinese, the single character 得 can represent two completely different grammatical items: a modal verb (děi) meaning 'must' or 'have to', and a particle (de) that attaches to a verb to introduce a complement describing how an action is performed or its result. Pronunciation is the key clue: děi always has the third tone and is a verb, while de is unstressed and acts as a structural particle. Negation patterns also differ: děi is negated with 不用 (bùyòng), while the de complement is negated by inserting 不 after 得 (e.g., 跑得不快). Confusing the two leads to grammatical errors and miscommunication.

Quando usare ciascuno

得dé

must (modal)

Use 得 (děi) to express necessity or obligation, often due to external circumstances (e.g., rules, schedules, or practical requirements). It behaves like a modal verb and is always followed by a verb or verbal phrase. It cannot be negated with 不; instead, the opposite meaning is conveyed by 不用 (bùyòng) or 不必 (bùbì).

得 (děi) is a defective verb: it does not take aspect markers like 了, 着, or 过, and it cannot be reduplicated. In some northern dialects, 得 (děi) may have a different tone sandhi, but standard Mandarin treats it as third tone.

得dé

(complement marker)

Use 得 (de) after a verb to introduce a complement that describes the degree, result, or manner of the action. The complement is typically an adjective or a phrase. The structure is 'Verb + 得 + Adjective/Phrase'. To negate, insert 不 after 得 (e.g., 跑得不快). It is a neutral-tone particle and cannot stand alone.

Do not confuse this with the potential complement structure (e.g., 跑得快 'can run fast' vs 跑不快 'cannot run fast'), where 得 is infixed and has different negation rules. The complement marker 得 (de) always appears between the verb and the complement, and the verb itself can be monosyllabic or polysyllabic.

In sintesi

	得	得
Pronunciation	děi (third tone)	de (neutral tone)
Part of speech	Modal verb	Structural particle
Meaning	Must, have to	Links verb to complement of degree/result
Negation	不用 + verb (e.g., 你不用去)	Verb + 得不 + Adj (e.g., 跑得不快)
Followed by	Verb or verb phrase	Adjective or descriptive phrase
Typical structure	Subject + 得 + Verb	Subject + Verb + 得 + Complement

Esempi

得
我得走了。
Wǒ dé zǒu le.
I have to go now.
děi expresses necessity (external reason – meeting time).
得
他跑得很快。
Tā pǎo dé hěn kuài.
He runs very fast.
de links the verb 跑 to the complement 很快.
得
你不用担心，我得自己做。
Nǐ bú yòng dān xīn, wǒ dé zì jǐ zuò.
You don't need to worry; I have to do it myself.
得 (děi) is negated with 不用, not 不.
得
她说得不对。
Tā shuō dé bú duì.
She didn't say it correctly.
Negation: 不 is placed after 得, not before it.
得
你得先完成作业再玩。
Nǐ dé xiān wán chéng zuò yè zài wán.
You must finish your homework before playing.
děi indicates a rule or necessity.
得
他跑得不快，但很稳。
Tā pǎo dé bú kuài, dàn hěn wěn.
He doesn't run fast, but he is very steady.
Correct negation of 得 (de) complement: 跑得不快, not 跑不快.

Errori comuni

Using 得 (děi) with 不 to negate (e.g., 不得去) – correct negation is 不用去.
Pronouncing the complement marker 得 (de) as děi, which changes the meaning (e.g., 他跑得很快 sounds like 'he must run fast').
Negating the complement structure 得 (de) as 'Verb + 不 + Adj' (e.g., 跑不快) when you intend to negate the degree complement – use 'Verb + 得不 + Adj' (e.g., 跑得不快).
Omitting 得 (de) when it is required after a verb before a degree/result complement (e.g., *他很跑快 for 他跑得很快).
Using 得 (de) after adjectives (e.g., *高兴得) – 得 only follows verbs (or stative verbs/psych verbs).

FAQ

How do I know if 得 is pronounced děi or de?: If the word means 'must' or 'have to' and is followed by a verb, it is pronounced děi (third tone). If it appears between a verb and a complement describing the action (e.g., 跑得很快), it is the particle de (neutral tone). Context and grammar always indicate the correct pronunciation.
When do I use 得 (děi) vs 得 (de)?: Use 得 (děi) to express obligation or necessity (like 'must' in English). Use 得 (de) as a structural particle to link a verb to a complement of degree or result. They are completely different in function and pronunciation, so you cannot substitute one for the other.
How do I negate a sentence with 得 (děi) and with 得 (de)?: To negate 得 (děi), use 不用 (bùyòng) before the verb (e.g., 你不用去 'You don't have to go'). To negate a complement with 得 (de), put 不 after 得 (e.g., 他跑得不快 'He doesn't run fast'). Do not use 不 before 得 in either case.
Can I use 得 (de) in potential complements like 跑得快?: The potential complement construction (Verb + 得 + Result, e.g., 跑得快 'can run fast') uses a different grammatical 得 (same character, but often considered a separate usage). Its negation is Verb + 不 + Result (e.g., 跑不快). This is not the same as the degree complement marker discussed here. Do not mix the negation patterns – for degree complements, always use 得不.