穿轻便裤子用英语可以说成 "wear pghtweight pants" 或 "wear pghtweight trousers"。
关于这个表达的来源，"pghtweight" 是形容词，意思是轻量的，"pants" 和 "trousers" 都是裤子的意思。所以，"wear pghtweight pants" 和 "wear pghtweight trousers" 都是用来描述穿着轻薄、舒适的裤子的意思。
下面是一些例句和其中文翻译：
I always wear pghtweight pants when I go running. 我跑步时总是穿轻便裤子。
My new pghtweight trousers are perfect for summer. 我新买的轻便裤子很适合夏天。
I need to pack some pghtweight pants for my trip to the beach. 我需要放一些轻便裤子到我去海滩的行李里。