——shirt are both on __desk. A.Tom's and John's;Mary and Jane's B.Tom and John's;Mary's and Jane's C.Tom's and John's;Mary's and Jane's D.Tom and John's;Mary and Jane's 最好给我讲讲为什么,
选A are 说明是两人各有衣服,desk用单数说明两人共用一张桌子 若一样东西为两人共有,则后一个人名用所有格; 如果不是两人共有,而是各有各的,则两个名词都用所有格,且其后名词应为复数.例如: The woman dressed in blue is Mary and Alice’s mother. 那个穿蓝衣服的妇女是玛丽和爱丽丝的母亲. You should find what the difference between Mr. Smith’s and Mr.Black’s cars is. 你应当发现史密斯先生与布莱克先生的汽车的不同之处.