| 一瞬 | yī shùn | one instant; very short time; the twinkle of an eye |
| 一并 | yī bìng | to lump together; to treat along with all the others; o treat along with all the others |
| 一味 | yī wèi | blindly; invariably |
| 一刀切 | yī dāo qiē | lit. to cut all at one stroke (idiom); to impose uniformity; one solution fits a diversity of problems; one size fits all |
| 一分为二 | yī fēn wéi èr | one divides into two; to be two-sided; there are two sides to everything; to see both sb's good points and shortcomings (idiom) |
| 一年四季 | yī nián sì jì | four seasons of the year |
| 一统 | yī tǒng | to unify; unified |
| 一成不变 | yī chéng bù biàn | nothing much changes (idiom); always the same; stuck in a rut |
| 一条龙 | yī tiáo lóng | lit. one dragon; integrated chain; coordinated process |
| 一把抓 | yī bǎ zhuā | to attempt all tasks at once; to manage every detail regardless of its importance |
| 一心一意 | yī xīn yī yì | intently |
| 一丝不苟 | yī sī bù gǒu | not one thread loose (idiom); strictly according to the rules; meticulous; not one hair out of place |
| 一般说来 | yī bān shuō lái | generally speaking; in general |
| 一天到晚 | yī tiān dào wǎn | all day long; the whole day |
| 一帆风顺 | yī fān fēng shùn | single sail, gentle wind (idiom); plain sailing; to go smoothly |
| 一本正经 | yī běn zhèng jīng | in deadly earnest; deadpan |
| 一目了然 | yī mù liǎo rán | obvious at a glance (idiom) |
| 一晃 | yī huǎng | (of passing time) in an instant; (of a sight) in a flash |
| 一模一样 | yī mú yī yàng | exactly the same (idiom); carbon copy |
| 一干二净 | yī gān èr jìng | thoroughly (idiom); completely; one and all |
| 一视同仁 | yī shì tóng rén | to treat everyone equally favorably (idiom); not to discriminate between people |
| 一举两得 | yī jǔ liǎng dé | one move, two gains (idiom); two birds with one stone |
| 一个劲儿 | yī gè jìnr | erhua variant of 一个劲, persistently; continuing |
| 一清二楚 | yī qīng èr chǔ | to be very clear about sth (idiom) |
| 一席话 | yī xí huà | what is said during a conversation; an utterance |
| 一眨眼 | yī zhǎ yǎn | in a wink |
| 一败涂地 | yī bài tú dì | failed and wiped over the floor (idiom); to fail utterly; a crushing defeat; beaten and in a hopeless position |
| 一览 | yī lǎn | an overview; at a glance |
| 一元论 | yī yuán lùn | monism, belief that the universe is made of a single substance |
| 一如既往 | yī rú jì wǎng | just as in the past (idiom); as before; continuing as always |
| 一意孤行 | yī yì gū xíng | isolated and stubborn; obstinately clinging to one's course; willful; one's own way; dogmatic |
| 一清早 | yī qīng zǎo | early in the morning |
| 一无所知 | yī wú suǒ zhī | not knowing anything at all (idiom); completely ignorant; without an inkling |
| 一去不复返 | yī qù bù fù fǎn | gone forever |
| 一笔勾销 | yī bǐ gōu xiāo | to write off at one stroke |
| 一网打尽 | yī wǎng dǎ jìn | to catch everything in one net (idiom); to eliminate at one stroke; to solve the problem at one fell swoop |
| 一概而论 | yī gài ér lùn | (saying) lump different matters together |
| 一把手 | yī bǎ shǒu | working hand; member of a work team; participant |
| 一瞥 | yī piē | glance; glimpse |
| 一丝一毫 | yī sī yī háo | one thread, one hair (idiom); a tiny bit; an iota |
| 一脉相承 | yī mài xiāng chéng | traceable to the same stock (idiom); of a common origin (of trends, ideas etc) |
| 一五一十 | yī wǔ yī shí | lit. count by fives and tens (idiom); to narrate systematically and in full detail |
| 一口咬定 | yī kǒu yǎo dìng | to arbitrarily assert; to allege; to stick to one's statement; to cling to one's view |
| 一场空 | yī chǎng kōng | all one's hopes and efforts come to nothing; futile |
| 一窍不通 | yī qiào bù tōng | I don't understand a word (idiom); all Greek to me |
| 一筹莫展 | yī chóu mò zhǎn | to be unable to find a solution; to be at wits' end |
| 一蹶不振 | yī jué bù zhèn | one stumble, unable to rise (idiom); a setback leading to total collapse; ruined at a stroke; unable to recover after a minor hitch |
| 一会儿…一会儿… | yī huìr yī huìr | one moment... the next... |
| 一…也… | yī yě | only... |
| 一…就… | yī jiù | as soon as... |