Can’t help but (不禁)

Structure 不禁 + spontaneous reaction (verb)

不禁 (bùjīn) describes a reaction that comes out on its own, that you can’t hold back: "couldn’t help but…". 听到这个消息，我不禁笑了 = "on hearing the news, I couldn’t help laughing". It goes before the reaction verb (笑, 哭, 想起…). It’s somewhat literary; in everyday speech 忍不住 is used. Note: 禁 here reads jīn (first tone), not jìn.

Examples

听tīng到dào这zhè个ge消xiāo息xi，我wǒ不bù禁jīn笑xiào了le。
On hearing the news, I couldn’t help laughing.
看kàn到dào这zhè一yī幕mù，她tā不bù禁jīn流liú下xià了le眼yǎn泪lèi。
Seeing that scene, she couldn’t help shedding tears.
想xiǎng起qǐ小xiǎo时shí候hou，我wǒ不bù禁jīn笑xiào出chū声shēng来lái。
Remembering my childhood, I couldn’t help laughing out loud.

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.

This point and the other 370, with audio on every example, inside Wanyu.