In Mandarin Chinese, 你 (Pinyin: nǐ 🔊) means “you” (singular informal, like German du, Russian ты or Spanish tú) or “your”. This is probably the first Chinese pronoun everybody learns without even realising: the greeting 你好 (nǐ hǎo 🔊), 你 + 好, literally “you good?”, except this is not a question. (Nor, for that matter, is “how do you do”.)
According to Wiktionary, this character is a phono-semantic compound of semantic 亻, a radical form of 人 “person”, and phonetic 尔, which is a simplified form of 爾. Lawrence J. Howell in his Etymological Dictionary of Han/Chinese Characters gives a different explanation:
尓 (= 爾) (adhere) + 人 person → person with close and ongoing relations with oneself → you. Compare 儂. Note the variant form 儞.
Curiously (for us), in written Chinese there is a difference between feminine and masculine second-person pronouns:
In traditional Chinese, 你 may be used to specifically refer to a male person, while 妳 can be used for a female person. In simplified Chinese, only 你 is standard.
A combination of 你 “you” and 我 “I”, 你我 (nǐwǒ), rather unsurprisingly, means “you and I”.
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