不一定
bù yīdìng
Not necessarily
不一定 (bú yídìng) is used to express that something is not necessarily true or certain. It's a polite way to question an assumption or suggest that there might be other possibilities, without directly contradicting someone.
What does 不一定 (bù yīdìng) mean?
不一定 (bù yīdìng) means “not necessarily” in English. Word for word, it breaks down as “not certain.”
When to use it
Neutral and polite. It's a common way to gently disagree or offer a different perspective. If you want to be more direct, you might say 不对 (bú duì, “that's not right”), but 不一定 is softer. A common reply might be 为什么？ (wèishénme?, “Why?”).
How to pronounce it
Sounds like “boo yee-DING.” The first two syllables are rising tones, and the last is a falling tone. Note the tone change for 不 from bù to bú before a second tone.
Other ways to say it
- 也许吧yěxǔ bamaybe / perhaps
- 看情况kàn qíngkuàngit depends on the situation
- 不一定对bù yīdìng duìnot necessarily correct
Examples
他会来吗？不一定。
tā huì lái ma? bù yīdìng.
Will he come? Not necessarily.
学中文很难吗？不一定，只要你努力。
xué Zhōngwén hěn nán ma? bù yīdìng, zhǐyào nǐ nǔlì.
Is learning Chinese very hard? Not necessarily, as long as you work hard.
明天会下雨吗？不一定，天气预报说多云。
míngtiān huì xiàyǔ ma? bù yīdìng, tiānqì yùbào shuō duōyún.
Will it rain tomorrow? Not necessarily, the weather forecast says cloudy.
Pro tip: Remember the tone change for 不 (bù) when it precedes a second tone (like 一). It changes from a fourth tone to a second tone, becoming bú.
Related phrases
你说得对 · You're right有道理 · That makes sense可能吧 · Maybe
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