Possibility of Postponement of Demand- Demand for those commodities whose consumption can be postponed will be price elastic . As against this, those commodities that are urgently required and whose consumption cannot be postponed will have an inelastic demand .
i don't understand this
If the use of a commodity can be postponed then the commodity has higher elasticity because if the use of a commodity can be postponed then it simply means that the commodity is not a necessity to the user, so the change in demand due to change in it's price will be higher. For e.g. consumption of clothing may be postponed , therefore, a rise in it's price may lead to a larger fall in its demand. Hence, the demand for clothing may be elastic. However, the consumption of food items cannot be postponed. Therefore their demand is inelastic.