| 一一 | yī yī | one by one; one after another |
| 一下子 | yī xià zi | in a short while; all at once; all of a sudden |
| 一半 | yī bàn | half |
| 一技之长 | yī jì zhī cháng | (saying) skill or proficiency |
| 一旁 | yī páng | aside; to the side of |
| 一样 | yī yàng | same; like; equal to; the same as; just like |
| 一毛不拔 | yī máo bù bá | stingy (idiom) |
| 一般 | yī bān | same; ordinary; common; general; generally; in general |
| 一路平安 | yī lù píng ān | to have a pleasant journey; Bon voyage! |
| 一路顺风 | yī lù shùn fēng | to have a pleasant journey (idiom) |
| 一一对应 | yī yī duì yìng | one-to-one correspondence |
| 一一映射 | yī yī yìng shè | bijective map (i.e. map between sets in math. that is one-to-one and onto); one-to-one correspondence |
| 一丁不识 | yī dīng bù shí | illiterate, ignorant |
| 一丁点 | yī dīng diǎn | a tiny bit; a wee bit |
| 一下儿 | yī xiàr | erhua variant of 一下 |
一不做，
二不休 | yī bù zuò ,
èr bù xiū | don't do it, or don't rest (idiom); either give up, or go through to the end; Since we started, we must carry it through whatever happens.; in for a penny, in for a pound |
| 一丘之貉 | yī qiū zhī hé | jackals of the same tribe (idiom); fig. They are all just as bad as each other. |
| 一中一台 | yī zhōng yī tái | "one China, one Taiwan" (policy) |
| 一中原则 | yī zhōng yuán zé | One-China principle, the official doctrine that Taiwan is a province of China |
| 一串 | yī chuàn | strand |
| 一之为甚 | yī zhī wéi shèn | Once is enough (idiom) |
| 一之谓甚 | yī zhī wèi shèn | see 一之为甚 |
| 一九四九 | yī jiǔ sì jiǔ | 1949; year of the communist victory in China, the foundation of the PRC and of ROC in Taiwan |
| 一九四九年 | yī jiǔ sì jiǔ nián | 1949; year of the communist victory in China, the foundation of the PRC and of ROC in Taiwan |
| 一二八事变 | yī èr bā shì biàn | Shanghai incident of 28th January 1932, Chinese uprising against Japanese quarters of Shanghai |
一人得道，
鸡犬升天 | yī rén dé dào ,
jī quǎn shēng tiān | lit. when a man achieves the Dao, his poultry and dogs rise to Heaven (idiom); fig. to ride on sb else's success; Once one man gets a government position, all his cronies get in too; Once sb has cracked the problem, every Tom, Dick and Harry can do it |
| 一代 | yī dài | generation |
| 一来二去 | yī lái èr qù | gradually; little by little; in the course of time |
| 一个中国政策 | yī gè Zhōng guó zhèng cè | one China policy |
| 一个人 | yī gè rén | alone |
| 一个个 | yī gè gè | each and every one |
| 一个劲 | yī gè jìn | continuously; persistently; incessantly |
一个幽灵在欧洲游
荡 | Yī gè yōu líng zài Ōu zhōu yóu dàng | Ein Gespenst geht um in Europa.; the opening sentence of Marx and Engels' "Communist Manifesto" |
| 一个接一个 | yī ge jiē yī ge | one by one; one after another |
| 一个样 | yī ge yàng | same as 一样; the same |
| 一个萝卜一个坑 | yī gè luó bo yī gè kēng | lit. one turnip, one hole (idiom); fig. each person has his own position; each to his own; horses for courses |
| 一侧化 | yī cè huà | lateralization |
一传十，
十传百 | yī chuán shí ,
shí chuán bǎi | news pass quickly from mouth to mouth (idiom); an infectious disease spreads quickly (old meaning) |
| 一元 | yī yuán | single variable (math.); univariate |
| 一元醇 | yī yuán chún | methyl alcohol CH3OH |
| 一刀两断 | yī dāo liǎng duàn | lit. one knife to cut two segments (idiom); fig. to make a clean break; firm resolution to break off a relation |
| 一分钱 | yī fēn qián | cent; penny |
| 一分钱一分货 | yī fēn qián yī fēn huò | nothing for nothing; you get what you pay for |
| 一分钱两分货 | yī fēn qián liǎng fēn huò | high quality at bargain price |
| 一切事物 | yī qiè shì wù | everything |
| 一切就绪 | yī qiè jiù xù | everything in its place and ready (idiom) |
| 一则 | yī zé | on the one hand |
| 一匙 | yī chí | spoonful |
| 一千吨 | yī qiān dūn | 1000 tons |
| 一千零一夜 | Yī qiān líng yī yè | The Book of One Thousand and One Nights |
