4. You were washing the dishes as/while I was drying them. 5. Kate was speaking to the doctor when/while her mobile telephone rang. 6. We were discussing the film as/while Mary was looking through some magazines. 7. The waiter was carrying the tray when/while he dropped a glass. 8. Sam was crossing the road when/while he saw his friend at the bus stop. 9. Lin and Wendy were preparing for the test as/while the postman knocked at the door. 10. The child was eating soup when/while his mother was making salad.

Перевод задания: Выберите подходящий союз: when или while.

4. You were washing the dishes while I was drying them. (Ты мыл посуду, пока я вытирал её.)
5. Kate was speaking to the doctor when her mobile telephone rang. (Кейт разговаривала с врачом, когда зазвонил её мобильный телефон.)
6. We were discussing the film while Mary was looking through some magazines. (Мы обсуждали фильм, пока Мэри просматривала журналы.)
7. The waiter was carrying the tray when he dropped a glass. (Официант нёс поднос, когда уронил стакан.)
8. Sam was crossing the road when he saw his friend at the bus stop. (Сэм переходил дорогу, когда увидел своего друга на автобусной остановке.)
9. Lin and Wendy were preparing for the test when the postman knocked at the door. (Лин и Венди готовились к контрольной, когда почтальон постучал в дверь.)
10. The child was eating soup while his mother was making salad. (Ребёнок ел суп, пока его мать готовила салат.)

While употребляется для параллельно происходивших длительных действий; when — когда одно событие произошло на фоне другого.