1. This is my brother.(改为一般疑问句，并作肯定回答）    
________  _______your brother?  
Yes,                ________.
2. These are her friends.（改为否定句）  
These                _______her friends.
3. That is his book.（改为复数句）    
    _____     _____his________.
4. I am your grandfather.（改为否定句）    
I                  _______your grandfather.
5. Mary is my sister.（改为一般疑问句，并作否定回答）    
________  _______your sister?    
No,_________ _________.
6. He is my teacher.（对画线部分提问）    
   _______       ______he?