why does nail does not get rusted when it is kept in oil and boiling water????????????

@ Ashish: Good attempt. I have made a small correction.

Water and oxygen are two things which are necessary for rusting of iron. If anyone from it is not present rusting of iron can not take place.

In oil and boiling water rusting of iron do not take place Because in oil, oil cut the contact of iron nail from water (water vapor) present in atmosphere and in boiling water,boiling water cuts the contact of iron nail from oxygen present in the atmosphere, as the dissolved oxygen in the water gets expelled on boiling. Hence in this way when iron nail is kept in oil and boiling water it does not get rust.