this is my brother中的this是什么句子成分

this is my brother中的this是什么句子成分 This is Tony.( )is my brother This is my aunt Mary.（This）的句子成分 This man is (my brother).对my brother部分提问 this is my brother 改为否定句 This cap is for my brother This is my brother.(改为复数） This is my brother.改为复数形式 This is a photo of my brother This is my sister and this is my brother 能不能写成this is my sis This is your brother.中文是什么 This is my sister a什么that is my brother?