Not necessarily: 未必
Denies certainty rather than the fact itself: something may be true, but it does not follow. A shorter, more written equivalent of 不一定.
Structure
主语 + 未必 + （都／会／能）+ 谓语 ｜ 我看未必
Explanation
Chinese words in this text can be activated to show a dictionary gloss.
“Expensive things are not necessarily all good.” does not say that expensive things are bad. It says that being expensive does not guarantee being good — it denies an inference, not a fact. That is the difference between “not necessarily good” and “not good”.
The word is common in argument, where it answers an assumption: ， “Studying for a long time doesn’t necessarily mean studying well.” It can also stand alone as a reply that politely doubts what someone has said: ， “He says it will rain tomorrow, but I’m not so sure.”
is an adverb. It follows the subject and precedes , , or the predicate directly. Since it already expresses doubt, it does not combine with , and it does not form a … predicate. In speech is more frequent; is shorter and is the usual choice in writing.
Correct
Say each one out loud before moving on. The audio is a reference pronunciation, not a model to imitate exactly — match the tone contour, not the voice.
贵的东西未必都好。貴的東西未必都好。
Guì (fourth tone, falling) de (neutral tone) dōngxi (first tone, high and level) wèibì (fourth tone, falling) dōu (first tone, high and level) hǎo. (third tone, dipping)···
Expensive things aren’t necessarily all good.
他说明天会下雨，可是我看未必。他說明天會下雨，可是我看未必。
Tā (first tone, high and level) shuō (first tone, high and level) míngtiān (second tone, rising) huì (fourth tone, falling) xià (fourth tone, falling) yǔ, (third tone, dipping) kěshì (third tone, dipping) wǒ (third tone, dipping) kàn (fourth tone, falling) wèibì. (fourth tone, falling)···
He says it will rain tomorrow, but I’m not so sure.
每天学到很晚未必是好办法，休息也很重要。每天學到很晚未必是好辦法，休息也很重要。
Měitiān (third tone, dipping) xué (second tone, rising) dào (fourth tone, falling) hěn (third tone, dipping) wǎn (third tone, dipping) wèibì (fourth tone, falling) shì (fourth tone, falling) hǎo (third tone, dipping) bànfǎ, (fourth tone, falling) xiūxi (first tone, high and level) yě (third tone, dipping) hěn (third tone, dipping) zhòngyào. (fourth tone, falling)···
Studying late every night isn’t necessarily a good approach; rest matters too.
Incorrect — Common mistakes
These sentences are wrong. They are printed here on purpose, each one paired with the repair and the reason, because the error you can recognise is the error you stop making.
Not quite
Incorrect sentence: 未必贵的东西都好。
Correct
Correct sentence: 贵的东西未必都好。
Why: 未必 is an adverb: it follows the subject and comes before 都.
Not quite
Incorrect sentence: 他一定未必会来。
Correct
Correct sentence: 他未必会来。
Why: 一定 asserts certainty and 未必 denies it; the two cancel out. 未必 alone is the hedge.
Not quite
Incorrect sentence: 这个办法是未必好的。
Correct
Correct sentence: 这个办法未必好。
Why: 未必 modifies the predicate directly; it is not wrapped in 是…的.
Compared with
Most errors with this pattern are not errors about this pattern — they are a neighbouring pattern arriving at the wrong moment. Read these side by side.
不 and 没 deny the fact: 他不来 “he isn’t coming”, 他没来 “he didn’t come”. 未必 denies only the certainty: 他未必来 “he won’t necessarily come” leaves both outcomes open. When you want to push back on an assumption without claiming the opposite, 未必 (or spoken 不一定) is the precise word; 不 overstates the case.
Negation: 不 versus 没(有) →Mini quiz
Question 1 / 3Total score: 0
Fill the gap: 学的时间长，___ 学得好。