Annotation

All of the above studies are based on:
My textbook

​

www.baidu.com
www.google.com
http://fta.mofcom.gov.cn/article/fzdongtai/201512/29714_1.html
https://www.cnki.net/
https://www.un.org/zh/
https://www.investopedia.com/terms/n/nafta.asp