Secondly, native language can never be excluded in the foreign language learning．
Thirdly, a contrastive analysis between the differences and similarities of languages was recognized clearly towards the end of 19th century and the beginning of 20th century, especially in Europe．

II. The Standard Pronunciation of English and Chinese

2.1 Received Pronunciation of English
As the mother tongue of the United Kingdom, the United State and 103 other countries, English is to be understood that nobody can speak the same language exactly alike．For example, people from different places in China speak with different local accents. There are 20 vowels in English which can be pided into two parts:12 monophthongs (simple/pure vowels) and 8 diphthongs． 英语语音教学中的负迁移现象解析(2):http://www.751com.cn/yingyu/lunwen_39500.html