Lesson 4
http://www.hwjyw.com/textbook/dzjc/zh/cd1/main4/index.htm
Lesson 5
http://www.hwjyw.com/textbook/dzjc/zh/cd1/main5/index.htm
Lesson 6
http://www.hwjyw.com/textbook/dzjc/zh/cd1/main6/index.htm
Lesson 7
http://www.hwjyw.com/textbook/dzjc/zh/cd1/main7/index.htm
Lesson 8
http://www.hwjyw.com/textbook/dzjc/zh/cd1/main8/index.htm
Lesson 9
http://www.hwjyw.com/textbook/dzjc/zh/cd1/main9/index.htm
Lesson 10
http://www.hwjyw.com/textbook/dzjc/zh/cd1/main10/index.htm
Lesson 11
http://www.hwjyw.com/textbook/dzjc/zh/cd1/main11/index.htm
Lesson 12