Not that … not / may well (未尝不)

Structure 未尝不 + adjective/verb (indirect affirmation)

未尝 (wèicháng) is a literary "not", close to 未必 / 不曾, and on its own negates with a cultivated tone: 未尝有过 "has never happened". Its most characteristic use is the double negative 未尝不 (wèicháng bù), which makes a softened, indirect affirmation: 这未尝不是一件好事 = "this may well be a good thing after all". It amounts to "it could well be", "it's not that it isn't…": one concedes something cautiously without asserting it outright. It belongs to literary and essay register; compare 未必不 "not necessarily not".

Examples

换huàn个ge角jiǎo度dù看kàn，这zhè未wèi尝cháng不bù是shì一yī件jiàn好hǎo事shì。
Seen from another angle, this may well be a good thing after all.
他tā的de担dān忧yōu未wèi尝cháng没méi有yǒu道dào理lǐ。
His worry is not without grounds at all.
适shì当dàng的de压yā力lì，未wèi尝cháng不bù能néng转zhuǎn化huà为wéi动dòng力lì。
A moderate amount of pressure may well turn into a driving force.
类lèi似sì的de情qíng形xíng，历lì史shǐ上shàng未wèi尝cháng有yǒu过guo。
A comparable situation has never occurred in history.

Levels are indicative: they follow the standard Chinese Grammar Wiki (AllSet Learning) progression, not an official HSK 3.0 mapping. We never assign levels by eye.

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