People attend an open-air music concert at the Central Park in San Mateo, California, the United States, July 15, 2021. The 2021 Central Park Music Series kicked off here on Thursday. Starting from July 15 through Aug. 5, the city will hold a concert at the Central Park every Thursday. (Photo: Xinhua)

People attend an open-air music concert at the Central Park in San Mateo, California, the United States, July 15, 2021. The 2021 Central Park Music Series kicked off here on Thursday. Starting from July 15 through Aug. 5, the city will hold a concert at the Central Park every Thursday. (Photo: Xinhua)

People attend an open-air music concert at the Central Park in San Mateo, California, the United States, July 15, 2021. The 2021 Central Park Music Series kicked off here on Thursday. Starting from July 15 through Aug. 5, the city will hold a concert at the Central Park every Thursday. (Photo: Xinhua)

People attend an open-air music concert at the Central Park in San Mateo, California, the United States, July 15, 2021. The 2021 Central Park Music Series kicked off here on Thursday. Starting from July 15 through Aug. 5, the city will hold a concert at the Central Park every Thursday. (Photo: Xinhua)

A woman attends an open-air music concert at the Central Park in San Mateo, California, the United States, July 15, 2021. The 2021 Central Park Music Series kicked off here on Thursday. Starting from July 15 through Aug. 5, the city will hold a concert at the Central Park every Thursday. (Photo: Xinhua)

A man holding a baby attends an open-air music concert at the Central Park in San Mateo, California, the United States, July 15, 2021. The 2021 Central Park Music Series kicked off here on Thursday. Starting from July 15 through Aug. 5, the city will hold a concert at the Central Park every Thursday. (Photo: Xinhua)

A musician performs during an open-air music concert at the Central Park in San Mateo, California, the United States, July 15, 2021. The 2021 Central Park Music Series kicked off here on Thursday. Starting from July 15 through Aug. 5, the city will hold a concert at the Central Park every Thursday. (Photo: Xinhua)

People attend an open-air music concert at the Central Park in San Mateo, California, the United States, July 15, 2021. The 2021 Central Park Music Series kicked off here on Thursday. Starting from July 15 through Aug. 5, the city will hold a concert at the Central Park every Thursday. (Photo: Xinhua)

A woman with her pet dog attends an open-air music concert at the Central Park in San Mateo, California, the United States, July 15, 2021. The 2021 Central Park Music Series kicked off here on Thursday. Starting from July 15 through Aug. 5, the city will hold a concert at the Central Park every Thursday. (Photo: Xinhua)

People attend an open-air music concert at the Central Park in San Mateo, California, the United States, July 15, 2021. The 2021 Central Park Music Series kicked off here on Thursday. Starting from July 15 through Aug. 5, the city will hold a concert at the Central Park every Thursday. (Photo: Xinhua)

People attend an open-air music concert at the Central Park in San Mateo, California, the United States, July 15, 2021. The 2021 Central Park Music Series kicked off here on Thursday. Starting from July 15 through Aug. 5, the city will hold a concert at the Central Park every Thursday. (Photo: Xinhua)

A man attends an open-air music concert at the Central Park in San Mateo, California, the United States, July 15, 2021. The 2021 Central Park Music Series kicked off here on Thursday. Starting from July 15 through Aug. 5, the city will hold a concert at the Central Park every Thursday. (Photo: Xinhua)

A man attends an open-air music concert at the Central Park in San Mateo, California, the United States, July 15, 2021. The 2021 Central Park Music Series kicked off here on Thursday. Starting from July 15 through Aug. 5, the city will hold a concert at the Central Park every Thursday. (Photo: Xinhua)

People with their pet dogs attend an open-air music concert at the Central Park in San Mateo, California, the United States, July 15, 2021. The 2021 Central Park Music Series kicked off here on Thursday. Starting from July 15 through Aug. 5, the city will hold a concert at the Central Park every Thursday. (Photo: Xinhua)