shopping theme

docs/howtostudykorean/theme/index.md

@@ -29,7 +29,7 @@ In addition to the pile of sentences that will be provided, common words that re
 - [Unit 1: #1 – School](./school.md)
 - [Unit 1: #2 – Transportation](./transportation.md)
 - [Unit 1: #3 – Eating](./eating.md)
-- [Unit 1: #4 – Shopping](https://www.howtostudykorean.com/theme/shopping/ "(Theme) Unit 1: #4 – Shopping")
+- [Unit 1: #4 – Shopping](./shopping.md)
 - [Unit 1: #5 – Weather](https://www.howtostudykorean.com/theme/weather/ "(Theme) Unit 1: #5 – Weather")
 
 In time, we will continue to update more Theme Lessons to this Unit.