Listening 7. (No. 19~21)
https://www.youtube.com/watch?v=ikraOe6xtWo&list=PL6D-YTosvGYq8YexsOG53BGav1CD0t3aM&index=37
Listening 8. (No. 22~24)
https://www.youtube.com/watch?v=O36wclCTeQ0&list=PL6D-YTosvGYq8YexsOG53BGav1CD0t3aM&index=38