完整答案如下，保证准确率！
1. This pencil-box is mine.
= This is my pencil-box.
2. Those are their books.
= Those books are theirs.
3. I am Mary Green.
= My name is Mary Green.
4....
完整答案如下，保证准确率！
1. This pencil-box is mine.
= This is my pencil-box.
2. Those are their books.
= Those books are theirs.
3. I am Mary Green.
= My name is Mary Green.
4....