当你替换一个单词时，一定要确保你选择的替代词不会改变句子的意思。

In the description of the airplane＇s Propeller, if appropriate, feathering, unfeathering, and reversing shall be discussed.

In the description of the airplane＇s Propeller, the propeller and its operation if pitch can be varied shall be deseribed.

In the description of the airplane＇s Engine, abnormal operations should be discussed briefly. This should be held to the minimum that will help a pilot to correct a situation or enable him to describe it to a mechanic. It should not be a maintenance procedure.

In the description of the airplane＇s Engine, any gear reduction system in the engine shall be described.

In the description of the airplane＇s Engine, if an engine fire detection or extinguishing system is available, describe, give principle of operation, and explain how to use these.

In the description of the airplane＇s Engine, any unique engine mounts including shock mounts shall be described.

In the description of the airplane＇s Engine, the accessories shall be described simply including: 1.Oil pump 2.Fuel pump 3.Hydraulic pump 4.Air pump 5.Tachometer 6.Torque meter 7.Electrical power source 8.Propeller synchronizer 9.Exhaust gas temperature probe

In the description of the airplane＇s Engine, the cooling system including cowl flaps shall be described.

In the description of the airplane＇s Engine, the air induction system shall be described including: 1.Path of flow of the air 2.Icing protection 3.Filtering 4.Supercharging/Turbocharging 5.Restrictions, warnings, tips

In the description of the airplane＇s Engine, proper operation and care of the engine when new and after the break in period should be described.