句型转换，按要求完成下列各句。

1. I have a book to give you. (改为疑问句)

    _____ you have a book to give _____ ?

2. You should borrow 10￥from your friends.(改为否定句)

    You _____ _____ _____ 10￥from your friends.

3. She is a woman doctor.（改为复数句）

    _____ are _____ _____ .

4. To work out the problem is hard. (同义句）

    _____  is hard _____ work out the problem.

压入式通风有哪些优缺点？其适用条件是什么？