Every Chinese speaker knows 失败乃成功之母 (shī bài nǎi chéng gōng zhī mǔ) — "Failure is the mother of success." That single character 乃 (nǎi) does the heavy lifting: it replaces 是 (shì) to mean "is," but with a literary, authoritative weight you won't hear at the breakfast table. 乃 (nǎi) belongs in speeches, essays, famous proverbs, and news editorials — not casual conversation.
The grammar is straightforward: swap in 乃 (nǎi) where you'd normally use 是 (shì), and your sentence instantly sounds formal and declarative. Consider the example 此乃不争的事实 (cǐ nǎi bùzhēng de shìshí) — "This is an indisputable fact." The note here is crucial: 乃 (nǎi) is very formal, used in written language and set phrases. You'd reach for it when making powerful, authoritative statements — the kind that signal tradition and command respect. In everyday speech, 是 (shì) still does the job.
This is a live conversation lesson: you talk out loud with AI teacher Mei Lin in real time, by voice. Over roughly 10 minutes, you'll practice making formal declarations using 乃 (nǎi) in context — the kind of statements you'd use in a speech, debate, or essay. Mei Lin corrects your grammar and pronunciation in the flow of conversation and adapts to your level, so you get immediate feedback as you try the pattern yourself. The lesson targets this one grammar point, so by the end you'll know exactly when 乃 (nǎi) fits and when it doesn't. You can explore more HSK 6 lessons on related advanced patterns.
Your first lesson is free to try — no credit card required to start talking. To build muscle memory for the characters, you can also print handwriting sheets with the free Chinese worksheet generator. Ready for more advanced conversation practice? Try Softening Disagreement with 不过 (búguò) or Tentative Decisions with 姑且 (gūqiě).
乃 (nǎi) is a formal literary word that means "is," used in place of 是 (shì). It appears in speeches, essays, famous proverbs, and news editorials to make authoritative declarations — never in casual conversation. For example, 此乃不争的事实 (cǐ nǎi bùzhēng de shìshí) means "This is an indisputable fact."
Use 乃 (nǎi) only in formal contexts: written language, speeches, debates, and set phrases. It signals authority and tradition. If you're chatting with friends, stick with 是 (shì). The lesson "Stating Undeniable Truths" trains you to recognize exactly when 乃 (nǎi) fits and when it sounds out of place.
Each live conversation lesson targets one grammar pattern and takes roughly 10 minutes. You talk by voice with AI teacher Mei Lin, who corrects grammar and pronunciation as you go. The first lesson is free to try, with no credit card required to start talking.
Yes — you can print handwriting worksheets using the free Chinese Worksheet Generator. Ready-made packs cover HSK 1–3 words, so for an HSK 6 character like 乃 (nǎi) you'd generate a custom sheet. It's a good way to reinforce what you practiced in the live lesson.