Hehe, just kidding.
For boys, if you want to wear something loose, it is recommended to buy polyester fabric. Generally, the ratio of polyester to spandex is reasonable at 80% to 20%, because such fabrics are very good in perspiration, breathability and comfort. Adidas and Nike are basically using this matching principle now.
The same is true for girls, but girls' pants should be slightly close to the body, and only clothes that fit can wear a more perfect figure and confidence.