In some cases, the suffix 儿 is added to the word, but doesn’t change the meaning of the word.
玩 — 玩儿
儿 is most commonly used in the northern dialects, especially in the dialect in Beijing.
In Putonghua, erization is rarely used and usually modifies a word. You can use it for the following purposes:
1) to form a noun from a verb:
画 — 画儿
2) to form the diminutive form:
狗 — 狗儿
3) to change the meaning of words that consist of one character:
头 — 头儿 哪 — 哪儿
When typing a word with erization on a keyboard, the suffix must be written as a separate character. If the word is pronounced as "tour", you should type "tou er".
If r is preceded by vowels, the pronunciation of the syllable doesn't change. You just have to add the "r" sound at the end of the word. For example: 哪儿 , 好儿 .
If "r" is preceded by either n or ng, both "n" and "ng" are not pronounced in the syllable. Only "r" is pronounced.
wanr is pronounced as war: 玩儿 ;
kongr is pronounced as kor: 空儿 .
Consequently, there are a number of changes in the pronunciation of the syllables with the compound vowels "ian" and "üan".
ian is pronounced as ien. However, "n" is not pronounced in erization, so we should only pronounce ia. The pronunciation of “a” doesn't change.
dian is pronounced as dien: 点 ;
dianr is pronounced as diar: 点儿 .
üan is pronounced as üen, but "n" is not pronounced in erization, so we should only pronounce üa.
quan is pronounced as quen: 圈 ;
quanr is pronounced as quar: 圈儿 .