Yuen Ren Chao (traditional Chinese: 趙元任; simplified Chinese: 赵元任; pinyin: Zhào Yuánrèn; 3 November 1892 – 25 February 1982), also known as Zhao Yuanren, was a Chinese-American linguist, educator, scholar, poet, and composer, who contributed to the modern study of Chinese phonology and grammar. Chao was born and raised in China, then attended university in the United States, where he earned degrees from Cornell University and Harvard University. A naturally-gifted polyglot and linguist, his Mandarin Primer was one of the most widely used Mandarin Chinese textbooks in the 20th century. He invented the Gwoyeu Romatzyh romanization scheme, which, unlike pinyin and other romanization systems, can transcribe Mandarin Chinese pronunciation without needing diacritics to indicate tones.