см. тж. необходимо ~ не
• Be careful not to allow the air hose to become kinked.
• Care must be taken to align the ends of the wires correctly.
• Care should be exercised to see that there is no rundown ...
• One must be careful that the added circuits do not produce leakage currents.
• Ensure that good contact is maintained with the holders.
• It should be seen that the tubes are completely dry.
• Make ( or Be ) sure there is no collection of moisture.
• When adding the mercury see that nothing interferes with the free movement of the pen.
• Take care when the boss is welded on that the inside of the pipe does not become distorted by the heat.