I am going to Beijing, Shanghai and Hong Kong from March 17th to April 6th.

Lela, it's a bit cold in Beijing but warm in Shanghai and HK. The temperature ranges in these three cities are: 0 to 12 degrees celsius in Beijing, 8 to 18 degrees Celsius in Shanghai and 18 to 27 degrees Celsius in HK.

In Beijing, you need to wear overcoat, thin sweater and warm trousers. I went there in mid March. I remembered that I wore gloves and scarf when I climed the wall. In Shanghai, thin jacket, jeans and long sleeved t-shirts inside are ok.

In my view, a pair of sneaker or sports shoes is enough. In Beijing, you may wear a pair of thick socks if you are afraid of the coldness. In Shanghai and HK, you needn't worry because the temperature is high.