Defining and non-defining clauses

[Bassim]

Please, would you tell me if I written correctly the following sentences:

1. The doctors were unable to save the life of a man who had drowned in the river.
2.The old woman was violently attacked by a young criminal, who had escaped from the prison the same day.
3. As long as he lives, he would never forget the words which his father told him on his deathbed.
4.Peter had a terrible shock, which changed his life for ever.

[5jj]

1. The doctors were unable to save the life of a man who had drowned in the river.
2.The old woman was violently attacked by a young criminal, who had escaped from the prison the same day. That's possible, as is a defining clause without the comma.
3. As long as he lives, he would never forget the words which his father told him on his deathbed.
You choice of defining relative clause is fine. I would change 'lives' to 'lived' and 'told him' to 'said to him'. I would probably use 'that' rather than 'which'; in informal conversation I'd use nothing.
4.Peter had a terrible shock, which changed his life for ever.

5