You must take good care of the drainage cock of the air control systemBecause （） leads scale formed which might malfunction the pilot control valve and other instruments.
举一反三
- Which of the following hydraulic control valves belongs to pressure control valve （ ）. A: Unloading valve B: overflow throttle valve C: Hydraulic control check valve D: Low pressure selector valve
- If the control was adjusted , omit the valve test. A: If the control was<br/>adjusted before you started this procedure, do not do the valve test. B: If the control was adjusted previously, omit the valve test. C: Adjust the control prior to doing the valve test. D: The adjustment of the control has priority over the valve test.
- The air control system is based on radar, which means fewer planes can take to the skies.
- Children must _____ by their parents. A: be taken good care B: be taken good care of C: take good care D: take good care of
- The study says there must be a complete ______ of air traffic control systems.