How do we write when a syllable starting with i u and ü?

• When a syllable consists of i in ing only, y must be added in front of i.
  i — yi
  in—yin
  ing—ying

• When a syllable consists of ia ie iao ian iang iong only, the final i should be replaced by y.
  ia—ya
  ie—ye
  iao—yao

• When ü is located at the beginning of a syllable, y must be added in front of ü and the two dots on ü must be removed.
  ü —yu

• When a syllable consists of “u” only, “w” must be added in front of “u”.
  u—wu

• When u is located at the beginning of a syllable that carries more than one vowel, ”u”must be replaced by w.
  uo—wo
  uang—wang

Tips for reading: when you see “W”, you read “u”, when you see “Y” before “u”, you read them together as “ü”. When you see “Y” before other finals, you read it as “i”.