this is 【my shirt】针对划线部分提问 What is this?
this is not Mary's dress变为一般疑问句 Is this Mary's dress?
my shirt's 【blue】针对划线部分提问 What colour/color is your shirt?
that is tim's coat变为否定句 That isn't Tim's coat.
翻译
你的衬衫 your shirt
蒂姆的衬衫 Tim's shirt
也许是的 maybe yes