Correct punctuation is important because it shows how the different parts of the text are related and prevents ambiguity.

A. The portion of the system is used to eliminate or prevent the formation of ice on all airfoil surfaces, including wings and airfoil sections of the empennage.

B. The portion of the system is used to dispel or get rid of ice gathering on some aircraft surfaces, including wings and empennage surfaces.

C. The portion of the system is used to eliminate or forbid ice forming on outside parts of all airfoils, including the airfoils of wings and empennage.

A. Do not use verbs that are general and vague.

B. Do not use verbs that are normal and mixed.

C. Do not use verbs that are usual and blended..

A. The coating thickness must be more than 0.05mm and less than 0.06mm.

B. The thickness of the second coating layer must be 0.05mm and 0.06mm.

C. The thickness of primer layer must be between 0.05 mm and 0.06 mm.

A. 在释压测试期间，不得开启舱门。

B. 在增压测试期间，确保舱门关闭。

C. 进行水压测试时，确保舱门关闭。

A. When the indicator is visible, stop the pump.

B. When the indicator comes on , stop the pump.

C. Stop the pump unless the indicator comes into view.

A. 描述飞机电力转向系统时，如安装前轮电力转向，应包括以下相关信息： （a）系统 （b）如何使用 （c）限制讨论。

B. 描述飞机动力转向系统时，如安装前轮动力转向，应包括以下相关信息： （a）系统描述 （b）如何使用 （c）相关限制。

C. 描述飞机功率转向系统时，如果安装前轮功率转向，应包括以下相关信息： （a）应描述系统。 （b）应说明如何使用。 （c）应阐述限制。

A. Removing it with special material is necessary if you find corrosion.

B. If you find corrosion, remove it with the specified material.

C. If corrosion is found, change the material to remove it.

A. To know what you want to say and to use the words that give the wanted meaning shall always be assured.

B. In order to express the meaning that you want, always make sure that you know what you want to say and you use the words.

C. Always make sure that you use what you want to say to express the words with the meaning that you want.

A. Many electrical power components are in the EE compartment.

B. Many electrical power components are in the cargo compartment.

C. Many electrical power components are in the APU compartment.

A. 飞行员操作手册的本节应包含重要的补充材料（操作信息），以便安全有效地操作配备了各种选装系统和设备的标准飞机。

B. 为了安全顺畅地操作飞机，当标准飞机未配备选装系统和设备时，飞行员操作手册的本节应包含必要的补充材料（操作信息）。

C. 飞行员操作手册的本节应包含适当的补充材料（操作信息），以便在配备了标准飞机所没有的各种选装系统和设备情况下，安全有效地操作飞机。