The reason why the two-hole plug does not divide the zero line is that there is no positive and negative pole. The reason why the two-hole plug does not divide the zero line is that the 220V electrical appliance does not need the phase of the power supply. Generally, single-phase 220V electrical appliances do not distinguish between positive and negative polarities. Electrical appliances with two-pin plugs are relatively safe in design, and triangular plugs with ground wires are only used for electrical appliances with high power consumption or easy to get an electric shock.
Matters needing attention in using two-hole plug
If the two-hole plug is broken, it can still be used. As long as the metal wire inside is not exposed, it can still be used. There is no doubt about it, you can rest assured, but you must pay attention to safety. If there are two holes on it, it will cause insulation safety. So the best way is to wrap it with insulating tape, so you can continue to use it, don't worry.