What to wear in 6- 15 degree weather?

Cotton coat, sweater. The temperature is between 6 and 15 degrees. The principle of dressing is to keep warm. Wear cotton-padded clothes, sweaters, coats and other clothes. The collocation depends on the place. When outdoors or exercising, you can choose down jackets, sweaters, jeans, etc. And indoors or in an air-conditioned environment, you can choose some light T-shirts, sweaters or shirts.