Когда мальчик вошел в комнату, его

Когда мальчик вошел в комнату, его отец сидел у камина и читал письмо, которое он получил в его отсутствие.

Результаты (английский) 1:

When the boy entered the room, his father sat by the fireplace and read a letter he had received in his absence.

Результаты (английский) 2:

When the boy came into the room, his father sitting by the fireplace and read a letter he had received in his absence.

Результаты (английский) 3:

When the boy entered the room, his father was sitting in front of the fireplace and read letter, which he received in his absence.