"Grandma, can you take me to the mall today? I want to use my Christmas gift certificate to buy some clothes," asked Myli.
"Sorry, Myli. It's not our day to use the car. You'll have to wait until Saturday unless you can find another ride," answered Grandma.
"What do you mean 'It's not our day to use the car,' Grandma? It's your car. Why can't you use it anytime you want to?" she asked.
"Because it costs too much to drive to town every day. Grandpa and I are on Social Security. We must use our money wisely because we are on a fixed income. We save all our errands until Saturday, and that is when we use the car. We try to get everything done with one trip."
"What is Social Security?" asked Myli.