1. He was Tom. I met him at the bar yesterday

-> he was Tom whom I met at the bar yesterday

2. The children often go swimming on Sundays . They have much free time then

-> the children who have much free time then often go swimming on Sundays

3. They are looking for the man and his dog. They have lost the way in the forest

-> they are looking for the man and his dog who have lost the way in the forest