Tom is my friend.改为一般疑问句 This a key in English.(对划线部分提问）That

Tom is my friend.改为一般疑问句是Is Tom my friend?Be动词提到句子开头
This a key in English.(对划线部分提问）是What this in English?
That is my uncle.改为否定句 加否定词not 就为That is not my uncle
is not 缩写成为isn’t