建设单位在办理工程质量监督注册手续时需提供的材料包括( )。
A．施工图设计文件 B．工程招标文件C．施工、监理合同 D．施工许可证
参考答案：C
按要求改写下列句子。
1．She has been working for 20 hours.（改为一般疑问句，并作否定回答）
she working for 20 hours?No, .
2．I've been skating since l was six years old.（对画线部分提问）
you been skating?
3．Tom ran for one hour.（用现在完成进行时改写）
Tom for one hour.
4. We have been learning English for three years．（改为同义句）
We have been learning English .
5. I started playing tennis when I was seven years old. （改为同义句）
I started playing tennis seven.
什么是直流放大器的零漂现象？产生的原因是什么？如何克服？
