Скорее всего, данный вопрос задан к тексту, где указано, что эти люди делали, когда позвонили из полиции. Если интересует грамматика, то ответ, например, может быть таким. The Macwizards were playing cards when the police phoned The Macwizards were drinking tea when the police phoned The Macwizards were sleeping when the police phoned
The Macwizards were playing cards when the police phoned
The Macwizards were drinking tea when the police phoned
The Macwizards were sleeping when the police phoned