金属会引起磁干扰。

A. When the pressure decreases, lift the cover.

B. When the pressure increases, lift the cover.

C. When the pressure decreases, lift the covering.

A. 勤务包括为飞机提供适当的燃油和滑油的信息。

B. 勤务工作需要飞机的信息，以便提供适当的燃油和滑油。

C. 勤务需要相应的信息才可以给飞机提供足量的燃油和滑油。

A. The word given in the approved examples is not controlled

B. The word given in the approved examples is not mandatory

C. The word given in the approved examples is not a must

A. 调整倾斜仪，直到气泡位于中心。

B. 在倾斜仪上的气泡位于中心后进行调整。

C. 将倾斜仪调整到气泡的中心位置。

A. 戴上氧气面罩并进行呼吸，确认其供氧正常。

B. 在佩戴氧气面罩前进行深呼吸，确认血液中氧气充足。

C. 为确保供氧正常，请不要摘下氧气面罩并进行呼吸。

A. In such cases, the introduction should notice the systems related in the manual，manufacturers may also choose to group related systems where the simplicity of the product permits.

B. In such cases, the introduction should note the systems covered in the manual，manufacturers may also choose to group related systems where the simplicity of the product permits.

C. In such cases, the introduction should note the systems comprised in the manual，manufacturers may also choose to divide related systems if the product is simple enough.

A. Clean the surface to make sure that the sealing is satisfactory.

B. Clean surfaces to ensure the bonding as required.

C. Clean the surface to make sure that the bond is satisfactory.

A. This Specification is designed to provide guidance for the development of Handbooks for all types of general aviation airplanes. These airplanes are originally certificated at minimum takeoff weights of 12,500 pounds or more.

B. This specification is intended to provide guidance for the development of Handbooks for all types of general aviation aircraft, which are initially certificated at maximum takeoff weights of 12,500 pounds or less.

C. This specification is intended to provide guidance for the preparation of Handbooks. For all types of general aviation aircraft, their maximum take-off weight is more than 12,500 pounds.

A. Advisory circular must always be carried out on aircraft.

B. Advisory circular is the procedure that must be used when performing maintenance on an aircraft.

C. FAA provides advisory circular which is not always carried out on aircraft.

A. Even though this specification is conformed to recognized industry practices , it is prepared in broad genuine terms and it is recognized that problems will occur which are not handled enough by the specification.

B. Although this specification coheres with recognized industry practices , it is written in vast general terms and it is asserted that problems will appear which are not treated sufficiently by the specification.

C. Though this specification complies with accepted industry practice, it is compiled in wide generic terms and it is recognized that problems which are not treated adequately by the specification will arise.