There is no clear source. I was born in summer and witnessed my centenary birthday. How lucky I am. I wish the mountains and rivers peace and the motherland prosperity. I express my deep feelings and best wishes to the people of China and China. The phrase "How lucky I am to be born in China and witness the centenary" expresses my gratitude for being able to grow up in this great country of China and witness the historical development. "May the mountains and rivers be peaceful and the motherland be prosperous" expresses my best wishes for a more prosperous motherland.