Mettez ce récit au passé en marquant les antériorités

Tom opened the door of the flat and stopped. Someone had been there before him: the lamp was on, and a cup of tea was standing on the table, still warm. He called out, but nobody answered. Only later did he understand that his sister had come back from Australia.

Trois strates. Le prétérit simple fait avancer l'histoire (opened, stopped, called, answered) ; le prétérit continu pose le décor (was standing) ; le past perfect remonte au passé du passé (had been, had come). La dernière phrase demande en outre une inversion après only later — voir le chapitre de syntaxe.