If the temperature decreases to less than zero, drain the water system.

A. 每一节的文章都要有一份参考表格目录，以数字顺序列出各段落的标题。

B. 每一章节的内容都要有一份参考目录，以字母顺序标出各段落的主题。

C. 每一节的正文之前都要有一份目录，以页码顺序列出各段落的标题。

A. 与本规范的符合性相关的重要意见应予以公布。

B. 对于和本规范相抵触的重大意见应予以公布。

C. 应发布符合本规范的重要议题。

A. 配电系统包括通风沟、阀门、滑轨、热交换器、操纵装置等项目。不包括使用系统的供应阀。

B. 分配系统包括管道、阀门、作动筒、热交换器、控制器等。不包括输往用户系统的供应阀。

C. 分布系统包括排风管道、阀门、制动弹簧、热交换器、控制器等项目。不包括使用系统的供应阀。

A. 拧紧松紧螺套，直到钢索达到合适的张力。

B. 松开再拧紧螺套，直到钢索有适当的张力。

C. 旋转螺套，确保钢索处于正确的位置。

A. 组件延伸至壳体，安装并连接在通信控制组件上。

B. 组件延伸至壳体组件，并与伸缩控制组件相连。

C. 组件延伸至壳体组件，并与通讯控制组件相连。

A. 必要时，应使用示意图来指示“流量”，并以尽可能直接的方式说明空气控制、电气、流体动力、燃料和涡轮系统的操作。

B. 必要时，应使用示意图显示“工作流程 ”，简洁明了地显示气源系统、电源系统、液压系统、燃油系统和涡轮系统的运行。

C. 必要时应使用示意图，以表明“流向”，并以尽可能直接的方式说明空气控制、电气、流体动力、燃料和涡轮增压系统的操作。

A. The items in the Emergency Procedures check list are determined to be essential in aid of the pilot in an emergency and should be limited to the minimum number.

B. A limited number of items in the Emergency Procedures check list are determined to be essential to aid the pilot in an emergency.

C. To aid the pilot in an emergency, it is determined that the Emergency Procedures check list should contain only essential items.

A. Each door has flexible seals at its structure interface which protect the metal interfaces from damage by the airflow.

B. Each door has flexible seals at its structure interface which protect the metal interfaces from no damage by the airflow.

C. Each door has formalist seals at its structure interface which protect the metal interfaces from damage by the airflow.

A. The system interface circuits control the physical properties of the connected systems.

B. The system interface circuits adapt to the physical properties of the connected systems.

C. The physical configuration of the connected systems defies the behavior of the system interface circuits.

A. The rules containing in this specification shall provide a guide to the formatting, type and method of all present documents in the manufacturer＇s maintenance manual.

B. The rules in this specification are served as a guide for the format, style and way of representation for all materials contained in manufacturer＇s maintenance manual.

C. The rules contained in this specification shall serve as guides for format, style and method of presentation for all material included in maintenance manuals prepared by manufacturers.