株 On the HSK 7-9 vocabulary list, at CEFR level C2. zhū ㄓㄨ tree trunk stump (tree root) a plant classifier for trees or plants strain (biology) to involve others (in shady business) Sources CC-CEDICT, CC BY-SA 4.0 pinyinjs, Apache-2.0 国际中文教育中文水平等级标准, 中华人民共和国教育部, MIT