情不自禁

qíng bù zì jīn

unable to hold back

Character by character

情qíng
feeling

不bù
not

自zì
self

禁jīn
restrain

看到这一幕，她情不自禁地流下了眼泪。

Seeing this, she couldn't hold back her tears.

Tone: neutral.

Like 不由自主 but driven by emotion; 禁 is jīn, 'to bear'.

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