I am writing to complain about the unfair treatment that I received in your restaurant last FridayA. 就你们餐馆低劣的服务质量,我上周五已致信消协反映。B. 我在贵餐馆受到了不礼貌的待遇,我上周五已写信投诉。C. 我写此信是投诉上星期五在贵餐馆受到的不公正的待遇。