题目内容：

按要求改写下列句子，一空一词，含缩略词。

1.Jack has an eraser in his pencil case.（改为一般疑问）

Jack              an eraser in his pencil case?

2. I think tennis is very interesting.  （改为否定句）

I                             tennis is very interesting.

3. Her books are on the sofa.（对划线部分提问）

.             are              books?

4.There are old bikes under the tree.（变为单数句）

There                                old bike under the tree.

5.打乒乓球对我来说很简单。（完成译旬）

Playing ping-pong is                                 me．