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Free and secure accommodation, no bills and even the odd home-cooked meal. It sounds like the perfect living arrangement for cash-strapped(缺乏现金的) students. Two mothers believe they have devised a way for struggling students to save on accommodation costs when they leave home to study at university. Kate Barnham and Amanda Flude have launched Student Swaps, an online accommodation forum (论坛) for parents and students, in advance of the introduction in September of ￡3,000 higher education top-up fees. Their website says, “The principle behind Student Swaps is to enable students 填空 “永”字共（　　）画，第三画是（　　）。