yā​sǐ​luò​tuo​de​zuì​hòu​yī​gēn​dào​cǎo

the final straw

压死骆驼的最后一根稻草 壓死駱駝的最後一根稻草 yā​sǐ​luò​tuo​de​zuì​hòu​yī​gēn​dào​cǎo
the final straw
the straw that broke the camel's back; an idiom for a seemingly minor thing that causes a final collapse after many other burdens or problems