Lubricate the seal before its installation.

A. 原理图应倾向于处理整个系统，而不是附属系统。例如，空调系统，而不是空调系统内的压缩机。

B. 原理图应倾向于处理整个系统，而不是附件系统。例如，空调系统，而不是空调系统内的压缩机。

C. 原理图应尽量呈现整个总系统，而非各个子系统。例如，空调系统原理图不应把重点放在其中包含的压气机上。

A. 使用左边的开口，以方便接近。

B. 打开剩下的通道，以方便访问。

C. 通过右边的开口，以方便访问。

A. In some cases, for complex aircraft, special training should be conducted so that the aircraft and its systems can be maintained properly.

B. Sometimes, especially for complex airplanes, it may be necessary to provide specific training in the proper maintenance of the airplane and its systems.

C. Sometimes, for particularly complex airplanes, it is required to provide special training so as to perform proper maintenance of the aircraft and its systems.

A. Make sure that the hydraulic oil can be cleaned.

B. Make sure that there is no dust in the hydraulic fluid.

C. Make sure that the hydraulic fluid is uncontaminated.

A. 乘客座位所在区域以及自助餐/厨房、卫生间、休息室和更衣室中的照明子系统。包括直接和间接照明、主警示灯系统、警示灯调光系统等。

B. 乘客座位所在区域以及自助餐/厨房、卫生间、休息室和更衣室中的照明子系统。包括直接和间接照明、乘客阅读灯、机舱圆顶灯等。

C. 乘客座位所在区域以及自助餐/厨房、盥洗室、休息室和衣帽间中的照明子系统。包括直接和间接照明、乘客呼叫系统、照明标志等。

A. 膝盖连接处使钢筋板更加强劲。

B. 重叠接头使加固板强度更大。

C. 加强板可以增加搭接处的强度。

A. A servo system is a device that has the ability to carry out an order and give a response to fufill five basic requirements.

B. A servo system is a device that has the ability to carry out an order and give a response to orders. It can finish five basic requirements.

C. A servo system is a device that has the ability to respond to and carry out an order which must be able to fufill five basic requirements.

A. 用填隙片填充空隙并在临近的结构区域补封严胶胶。

B. 填隙片在临近结构区域填充空隙需要补封严胶。

C. 用密封胶填充补片和相邻结构之间的空隙。

A. Use a degreasing agent to remove oil and grease.

B. Draw oil and grease from a degreasing agent.

C. Add oil and grease into a degreasing agent.

A. 技术文本通常包含很长的词组，在句子中具有一种词性的作用。

B. 技术文本通常包含很多组单词，这些单词在句子中具有一定的作用。

C. 技术文本通常包含长难句，其中的单词在句子中的作用相当于某个词性。