Was/were+ V-ing
Started playing tennis→ was playing tennis →finished playing tennis→ Now
This time last year I was traveling in India.
What were you doing at 4 o’clock yesterday afternoon?
I was shopping when I met Peter.
What were you doing when the phone rang?
I was watching TV.
What did you do when the phone rang?
I stopped watching TV and answered the phone.
When I got home, they had dinner.
were having dinner.