Shirt underpants and autumn trousers have different definitions. Shirts and underpants generally refer to single clothes and trousers worn inside, and autumn trousers mainly refer to clothes worn in close-fitting positions to keep warm and cold. There are many differences between them, such as:
First, the materials are different. There are many kinds of materials for shirts and underwear, which can be polyester, silk, yarn and various chemical fibers, as well as denim, satin, cotton and linen. The autumn clothes and trousers will use more comfortable and breathable fabrics, such as pure cotton, polyester, wool and cashmere.
Second, the style is different. Shirts and underpants are fashionable, and they can be short-sleeved shorts. The neckline of a shirt is usually a stand-up collar or lapel, and a few are round neck or bald collar. Autumn trousers are long-sleeved trousers, and the neckline is not higher than the coat. Generally, it's a round neck or a V-neck.
Third, the clothes are different. Shirts and underwear can be worn by yourself or sandwiched between underwear and coat. Autumn clothes and trousers are generally worn by others.
Generally speaking, the definition of shirt underpants is relatively broad, while the scope of autumn trousers is relatively narrow, and autumn trousers can also be classified as shirt underpants.