一

yī

number HSK 1 #21

Meanings

A single horizontal stroke — the simplest character, representing one

Wǒ yǒu yī gè gēge.

I have one older brother.

Gěi wǒ yī bēi shuǐ.

Give me a glass of water.

Yī gè rén zǒu le.

One person left.

grammar

一 changes tone depending on the next word: yī before 4th tone becomes yí (一个 yí gè), before 1st/2nd/3rd tone becomes yì (一天 yì tiān).

culture

一 is considered a lucky number in Chinese culture, symbolizing unity and being first.

usage

一 can mean 'as soon as' in patterns like 一…就… (yī...jiù...): 他一来就走了 'He left as soon as he arrived.'

一 yī