The International Phonetic Alphabet /I/ is a short sound symbol. Its long sound symbol is added with ":"(/i:/). What is close to the Chinese "Yi" sound is actually a long sound. Short sounds are about one-fifth of the length of long sounds, and the pronunciation quality of /I/ is between "Yi" and "Yu". It should be noted that the English /I:/ sound is not exactly the same as the "clothes" sound. There is no special mouth shape requirement for the pronunciation of "one" in Chinese, and slightly opening is the most common. But English /I:/ requires a flat mouth and a slippery mouth.