13 words
| Word | Pinyin | Definition |
|---|---|---|
| 内鬼 | nèi guǐ | mole |
| 居高不下 | jū gāo bù xià | (of prices, rates etc) to remain high |
| 拦路虎 | lán lù hǔ | stumbling block |
| 毒瘤 | dú liú | malignant tumor |
| 滋生 | zī shēng | to breed |
| 滑铁卢 | Huá tiě lú | Waterloo moment |
| 肃清 | sù qīng | to purge |
| 落寞 | luò mò | lonely |
| 荡涤 | dàng dí | to clean up |
| 蛀虫 | zhù chóng | insect that eats into wood, books, clothes etc |
| 重灾区 | zhòng zāi qū | area particularly hard-hit by a disaster |
| 防火墙 | fáng huǒ qiáng | firewall |
| 鲜为人知 | xiǎn wéi rén zhī | rarely known to anyone (idiom); almost unknown |