Comparing "kending" "queding" and “yiding"

If you look up 肯定 (kěndìng), 确定 (quèdìng) and 一定 (yīdìng) in the dictionary, they all have similar meanings, like "certain" or "surely." However, using them correctly in a sentence is a bit more complicated.

Word Overview

So how are these three words words different? We can answer this question from two points of view:

1. From a "parts of speech" point of view:

• 肯定 can be a verb, an adjective and an adverb.

• 确定 can be a verb or an adjective.

• 一定 can be an adjective or an adverb.

2. From a "significance or meaning" point of view:

• 肯定 often has a subjective, energetic feel to it。 It carries meanings like 认可 (approval), 同意 (agreement), and 保证 (guarantee).

• 确定 carries a feeling of objectively describing a situation. It carries the meaning of 决定 (to decide, to resolve).

• 一定 as an adjective has really broad uses, so you need to pay attention to the specific times it's used in. As an adverb, it is often used to give a reinforcing tone.

• 肯定 and 确定 can both be verbs, but their use and meanings are different. 一定 cannot be used as a verb.

肯定 and 确定 as Verbs

Structure with 肯定

肯定 can express that something approval or affirmation, often used when a superior evaluates subordinates. When used this way, it should be followed directly by a noun or a phrase.

肯定 + Noun / Noun Phrase

肯定 can also be used to express "I am sure." When used this way it is usually a clause at the end of a sentence.

Subj. + (敢)肯定 + Sentences

Examples with 肯定

• 老板 肯定 了 我们 团队 的 工作。Lǎobǎn kěndìng le wǒmen tuánduì de gōngzuò.The boss approved our team's work.
• 如果 想 让 别人 肯定 你，你 就 要 好好 做。Rúguǒ xiǎng ràng biérén kěndìng nǐ, nǐ jiù yào hǎohǎo zuò.If you want others to approve of you, you have to do good work.
• 我 敢 肯定 这 就 是 他的 声音。Wǒ gǎn kěndìng zhè jiùshì tā de shēngyīn.I'm quite sure that this is his voice.

Structure with 确定

确定 has the meaning of "confirm" or "determine," and you may add a verb phrase after 确定 to indicate that something is already decided. In a question, 确定 can be used to ask if someone is "sure" or "certain."

确定 + Phrase / Sentence

Examples with 确定

• 我们 还 没有 确定 什么 时候 开始。Wǒmen hái méiyǒu quèdìng shénme shíhòu kāishǐ.We still haven't decided when to start.
• 已经 确定 了 三 个 人，还 差 一 个。Yǐjīng quèdìng le sān gèrén, hái chà yī gè.Three people have already been confirmed, and one more is needed.
• 你 确定 他 是 我们 要 找 的 人 吗？Nǐ quèdìng tā shì wǒmen yào zhǎo de rén ma?Are you certain he's the person we should look for?

Common Mistakes

• 我们 要 先 肯定 一 个 形式 才 能 开始 做。In this sentence, 肯定 needs to be followed by a noun or a noun phrase.Wǒmen yào xiān kěndìng yī gè xíngshì cái néng kāishǐ zuò.
• 我们 要 先 确定 一 个 形式 才 能 开始 做。Wǒmen yào xiān quèdìng yī gè xíngshì cáinéng kāishǐ zuò.We'll have to decide on a design before we can start working.

• 老板 肯定 了 最近 我 很 努力。In this sentence, "肯定" needs to be followed by a noun or noun phrase.Lǎobǎn kěndìng le zuìjìn wǒ hěn nǔlì.
• 老板 肯定 了 我 最近 的 努力。By changing the word order, we get a noun phrase instead of a verb phrase.Lǎobǎn kěndìng le wǒ zuìjìn de nǔlì.The boss approved of my recent hard work.

肯定 and 一定 as Adverbs

肯定 and 一定 can both be adverbs, and the grammar structures for both are similar. 肯定 emphasizes more of a subjective judgment or assurance. 一定 sometimes carries a bossy air, useful when issuing a command.

Structure with 肯定

肯定 + Adj. / Verb

Examples with 肯定

• 他 肯定 还 没 起床，因为 他 的 手机 现在 还 没 开机。Tā kěndìng hái méi qǐchuáng, yīnwèi tā de shǒujī xiànzài hái méi kāijī.He definitely hasn't gotten out of bed yet， because his phone is still off.
• 这 次 我 肯定 不 骗 你，骗 你 是 小 狗，好 吧？The idiom 骗你是小狗 literally means "to deceive you is to be a small dog." It doesn't have a good English equivalent.Zhè cì wǒ kěndìng bù piàn nǐ, piàn nǐ shì xiǎogǒu, hǎo ba?I'm not lying this time. Cross my heart.

Structure with 一定

一定 + Adj. / Verb

Examples with 一定

• 明天 你们 一定 要 来。Míngtiān nǐmen yīdìng yào lái.You guys definitely have to come tomorrow.
• 一定 要 小心。Yīdìng yào xiǎoxīn.You've absolutely got to be careful.

Common Mistakes

• 你们 肯定 要 去 听 我 的 演唱会。Since it's a command, "肯定" is not appropriate.Nǐmen kěndìng yào qù tīng wǒ de yǎnchàng huì.
• 你们 一定 要 去 听 我 的 演唱会。Nǐmen yīdìng yào qù tīng wǒ de yǎnchàng huì.You guys totally have to go listen to me in concert.

肯定, 确定, and 一定 as Adjectives

All three of these can be placed before a noun as adjectives. But in this grammar structure, 肯定 and 确定 use their verb meanings, and 一定 as an adjective means "something particular."

Structures

肯定 + （的 +） Noun

确定 + （的 +） Noun

一定 + （的 +） Noun

Examples

• 如果 你 问 我 是 不 是 知道 这 件 事情，我 的 回答 是 肯定 的。Rúguǒ nǐ wèn wǒ shì bù shì zhīdào zhè jiàn shìqíng, wǒ de huídá shì kěndìng de.If you ask me if I know about this, my answer will be certain.
• 请 给 我 一 个 确定 的 回答，不 要 总是 这么 模糊。Qǐng gěi wǒ yī gè quèdìng de huídá, bùyào zǒng shì zhème móhú.Please give me a definite response. Don't always be so vague.
• 我们 之间 要 保持 一定 距离。Wǒmen zhī jiān yào bǎochí yīdìng jùlí.We need to keep a certain distance between us.
• 这 件 事 和 他 有 一定 的 关系，不 能 都 怪 你。Zhè jiàn shì hé tā yǒu yīdìng de guānxì, bù néng dōu guài nǐ.He has a certain connection with this matter. We can't completely blame you.

Sources and further reading

Books

• HSK Standard Course 4上 (pp. 55) Anything Goes (无所不谈) →buy

• 对外汉语教学语法释疑201例 (pp. 180) [ →buy]

• 现代汉语八百词（增订本） (pp. 603) [ →buy]

• 卓越汉语－公司实战篇 (pp. 5) 卓越汉语－公司实战篇 →buy

Dictionaries

• 现代汉语词典（第5版） (pp. 776, 1594, 1136) 卓越汉语－公司实战篇 →buy

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