阅读下面材料，在空白处填入适当的内容（不多于3个单词）或括号内单词的正确形式。
Mary: I(tell) that you've just been back from the USA. Will you tell me something about   the students there spend their summer vacation?
Jack: OK, In the United States, summer is the season of swimming pools, barbecues, camping and road trips. Road trip vacations are    (particular) popularwithcollege students, and   like to explore the country on wheels.    best part about car trips is that you can stop and explore if you are  (interest) in things you see along the way. And you don't have to plan  advance. You can just get into a car and drive.
Mary: What about the expense?
Jack: Evenwithhighgasprices, drivingwithfriends is  (cheap) than flying.
Mary: But what can one do   he or she doesn't have a car?
Jack: Though many college students don't own a car, most have access to one. I once used a  (borrow) car traveling from New York to New Orleans.