To travel by plane to Sanya__ (cost) you a lot of money during the festival next month.
问题描述：
To travel by plane to Sanya__ (cost) you a lot of money during the festival next month.
答
答案是【costs】
由于主语是to不定式,因此谓语动词记得用第三人称单数
翻译：下个月再节假日坐飞机去三亚会花掉你很多钱的.