bend forward and backward
Chinese idiom, Pinyin is Qi á NF ǔ h ò uy ǎ ng, which describes the body shaking back and forth (mostly refers to laughing).
Idiom usage
It's an adverbial to describe laughing. Xiaoming told a joke, which made the whole class laugh.
Analysis of Idioms
The synonym roars with laughter; the antonym laughs in silence
bend forward and backward
dust has covered kitchen utensils and fish has spawned in cooking vessels because of long disuse - zēng chén fǔ yú
the declining age is like a candle in the wind - fēng zhú zhī nián
Better a broken jade than a broken one - nìng kě yù suì,bù néng wǎ quán
profound sentiments of friendship - shēn qíng hòu yì