韧劲

tā gàn tuī xiāo zhè xíng quē shǎo zú gòu de rèn jìn

她干推销这行缺少足够的韧劲。

She's not tough enough for a career in sales.

tā jù yǒu chéng gōng shāng rén suǒ xū de rèn jìn

他具有成功商人所需的韧劲。

He has the tenacity of a successful businessman.