The pinyin of "Xiao Niu Er" should be spelled as "Xi m \u oniúer".

The pronunciation rules of Hua Er Yin also have certain requirements. The normal understanding is to add r after a sound, that is, to read with your tongue tilted up.

Cioni ur

A vowel with retroflex is called "retroflex rhyme", which is marked by adding R after vowel. The vowels that follow are still syllables, but the vowels with rhyme are usually written by two Chinese characters, such as Yu Er (yùr) and Lao Ren (L∥ otó ur).