How do you answer 'describe your last job' in an interview?

Think of a time when there was a problem on your job and you assisted in solving it. Then explain the scenario to your interviewer. For example, you are a cashier at McDonald's and a customer complained that he received cold french fries. You helped by giving the customer a fresh order of hot fries. Therefore, you response in your interview could be: "Whenever there are issues I try to solve them in a quick and timely manner. For instance, while working as a cashier at McDonald's I had an unsatisfied customer who complained of receiving cold french fries. I apologized to the customers and gave him a fresh order of hot fries. The customer left happy because I addressed his needs in a positive and quick manner."