Exercises to practice!

https://www.perfect-english-grammar.com/past-continuous-exercise-1.html

https://www.perfect-english-grammar.com/past-continuous-exercise-2.html

https://www.perfect-english-grammar.com/past-continuous-exercise-4.html

https://www.perfect-english-grammar.com/past-continuous-exercise-3.html

DESCRIBE WHAT THEY ARE DOING!