一道难题，求学霸指点，谢谢

Once there were two mice. They were friends. One mouse lived in the country;  the other mouse lived in the city. After many years the Country mouse saw the  City mouse; he said, "Do come and see me at my house in the country." So the  City mouse went. The City mouse said, "This food is not good, and your house  is not good. Why do you live in a hole in the field? You should come and live  in the city. You would live in a nice house made of stone. You would have nice  food to eat. You must come and see me at my house in the city."
The Country mouse went to the house of the City mouse. It was a very good  house. Nice food was set ready for them to eat. But just as they began to eat  they heard a great noise. The City mouse cried, " Run! Run! The cat is  coming!" They ran away quickly and hid.
After some time they came out. When they came out, the Country mouse said,  "I do not like living in the city. I like living in my hole in the field. For  it is nicer to be poor and happy, than to be rich and afraid.