Read the passage and answer the questions

After retiring, my uncle – a lover of the sea- took up a strange leisure activity: he spends most mornings at the beach, looking for things that the sea sends ashore. He says: “It’s a multi-beneficial leisure activity. I can get some exercise, blending, picking up, and walking. I can breathe the fresh air and enjoy the vastness and quietness of the sea. Sometimes I watch the children playing beach games and I feel years younger. At the same time, I can also clean the beach. It’s volunteer work, isn’t it? Many of the things I pick up from the beach are still useful to someone. I clean them and sell them at the Sunday flea market in the town nearby.”

How does he feel watching the children playing beach games?