Suppose the price elasticity of demand for heating oil is 0.2 in the short run and 0.7 in the long run.
If the price of heating oil rises from $1.80 to $2.20 per gallon, the quantity of heating oil demanded in the short run will by in the short run and by in the long run. The change is in the long run because people can respond easily to the change in the price of heating oil.