People wait for the green light near the railway station in Burlingame, California, the United States, Feb. 16, 2021. The San Mateo County, where the Burlingame locates, is still in the strictest control, or purple tier. (Xinhua/Wu Xiaoling)

A dog waits for its owner outside a coffee shop on a business street in Burlingame, California, the United States, Feb. 16, 2021. The San Mateo County, where the Burlingame locates, is still in the strictest control, or purple tier. (Xinhua/Wu Xiaoling)

People walk on a crossing near the railway station in Burlingame, California, the United States, Feb. 16, 2021. The San Mateo County, where the Burlingame locates, is still in the strictest control, or purple tier. (Xinhua/Wu Xiaoling)

A business street is seen in Burlingame, California, the United States, Feb. 16, 2021. The San Mateo County, where the Burlingame locates, is still in the strictest control, or purple tier. (Xinhua/Wu Xiaoling)