a. People were dancing when the lights went off.
b. The suspect was trying to leave the country when the police were catching him at the train station.
c. The accident was occurring when I was playing video games.
d. The police forces were transferring the suspect to his prison cell when a bunch of bad guys were attacking the vehicle.
e. Sherlock Holmes was reading the newspaper while Watson an Lestrade were cross-examining the suspect.
Voilà j’espère que ça aidera : )