Engines 1 and 2 supply hot air to their related wings.

A. Do not make the pressure became less than (or more than) 20 psi.

B. Do not let the pressure become less than (or more than) 20 psi.

C. Do not let the pressure close less than (or more than) 20 psi.

A. When preparing dangerous goods, follow the operational instructions.

B. Before you use dangerous materials, obey these precautions.

C. Prior to applying any hazardous material, understand the principles of it.

A. 飞机的五大结构包括机身，机翼，副翼，升降舵和起落架．

B. 飞机包括五个主要结构单元，它们是机身，机翼，安定面，飞行操纵舵面和起落架．

C. 飞机主要有五个结构部分，它们是机头，机翼，副翼，升降舵和起落架．

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. 程序应在每章内按编号顺序进行准备，并有适当的主次科目标题，无需从新的页面开始。

B. 程序应在每章内按照主次标题和参考号的形式进行编写，不需要从新的页面的开头开始。

C. 程序应在每章内按参考编号顺序编制，并有适当的主、副标题，而无需从新页的顶部开始。

A. By way of the control unit, enter the opening in the side of the tank.

B. Get access to the control unit through the opening in the side of the tank.

C. Get access to the control unit by opening one side of the tank.

A. 长期的配平是通过垂直安定面运动实现的。

B. 水平安定面的运动是通过径向配平实现的。

C. 水平安定面的运动可以实现径向配平。

A. 这个日期模块告诉你如何操作这个单位。

B. 这个数据模块告诉你如何计算这个单元。

C. 这个数据组件告诉你如何操作这个装置。

A. 冷却组件用来冷却风扇管道中的空气。

B. 点火组件是由来自风扇涵道的空气进行冷却的。

C. 加热组件是在风扇涵道的空气里进行冷却的。

A. If you find cracks, refer to the table that follows.

B. If you find dents, refer to the table that follows.

C. If you find scratches, refer to the table that follows.