一、英语课上刘同向同桌李华介绍了自己所带的家人物品照片。请读对话，仿照示例，圈出有关物品归属的表达。
Li Hua: Liu Tong, these dolls are cute. Whose are they?
Liu Tong: They're my little sister, Liu Nian's. She likes dolls very much.
Li Hua: What about the Chinese chess?
Liu Tong: It's my grandparents'.
Li Hua: Do they often play it?
Liu Tong: Yes, they do. They often play Chinese chess after dinner.
Li Hua: What a nice guitar!
Liu Tong: Yeah, it's my mother's.
Li Hua: Does she like playing the guitar?
Liu Tong: Yes, she does.
Li Hua: Does she play it every day?
Liu Tong: No, she doesn't. She plays it every Friday evening.
Li Hua: Whose ball is this?
Liu Tong: Ha ha. It's my dog and my cat's!

二、将你在上面对话中圈出的部分按照下面的分类填写在表格中。

总结：在表示物品所属关系时，通常要在单数名词和不以 -s 结尾的复数名词后加________；
在以 -s 结尾的复数名词后加________。

Liu Nian’s, my mother’s, my dog and my cat’s
; my grandparents’
; 's
; '