It is a refrigerator.
Because we have to save our foods.
But if we don't have refrigerator,
we can't eat foods.
Food is the most important!
And we can use refrigerator to air conditioner.=And we can use the refrigerator as air conditioner.
Because when we open it,
in there,
there are much chilly air,=Because when we open it,there is  much chilly air.
So refrigerator is the most important thing.