In this task, you're given an article and an answer. Your task is to generate the fill-in-the-blank question for this answer based on the given article. The blanks are always at the end of the question, and can be filled with more than one word or phrase.
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Question: Article: In some parts of the United States, farming is easy. But farming has always been difficult in the northeastern corner of the country, which is called New England. New England has many trees and thin, rocky soil. Anyone who has wanted to start a new farm there has had to work very hard. The first job has been cutting down trees. The next job has been digging the stumps of the trees out of the soil. Then the farmer has had the difficult job of removing stones from his land. This work of removing stones never really ends, because every winter more stones appear. They come up through the thin soil from the rocks below. Farmers have to keep removing stones from the fields. Even today, farms which have been worked on for 200 years keep producing more stones. That is why stone walls are used instead of fences around New England fields. The stone walls are not high; a man can easily climb over them. But they keep the farmer's cows from joining his neighbor's cows.
Answer: why there are many stone walls in New England

Answer: This selection explains _ .

Question: Article: Study Books Basic Study Manual Hardcover :$ 37 Future success depends on the ability to learn. Here are the answers to the questions most often asked by parents, teachers, business trainers and by students themselves. Read this book and learn: What the three barriers to study are and what to do about them. What to do if you get tired of a subject you are studying. Twenty-six simple drills to help you learn how to study easily, rapidly and with full understanding. Buy and read Basic Study Manual and use it do dramatically improve your ability to study. Study Skills for Life Hardcover: $32 L. Ron Hubbard's study technology for children opens the door to their future success by giving them the ability to study and learn. Fully illustrated (,) for easy comprehension. Learning How to Learn Hardcover: $25 The basics of effective study for 8 to 12-year-olds, fully illustrated. Children who read and apply the materials in this book regain their liking for study and their ability to apply this knowledge in life. Get this book for a child you want to see win at his studies! How to Use a Dictionary Picture Book for Children Hardcover: $36 In spite of billions of dollars spent on "educational research", children are not taught the most basic skills of learning, even the most basic of these: how to use a dictionary. In fact, a research of educational books for children found no book that told them how to use a dictionary or that one should. Written for children 8 to 12-year-olds, this fully illustrated book will teach your child: How to find words in a dictionary. The different ways that words are used. What the different marks and symbols that are used in a dictionary mean. How to use a dictionary to correctly pronounce words. It includes a section for parents and teachers showing you how to use this book with children. Buy this book and give it to your children to unlock their education. What's more, you will just pay 50% for it before May 1, 2014.
Answer: children

Answer: According to the advertisements, the four books are all intended for _ .

Question: Article: The best way to cure sadness is not shopping, according to a recent study. The so-called shopping method has become common practice these days, but that can put your wallet under a lot of pressure. So if you are sad and feel like shopping, don't! According to the recent study, sadness leads to self-focus thinking. In other words, sad people are willing to spend more money on the same thing than calm people. "It is the result of sadness and self-focus, and it turns out that sadness leads to an increase in self-focus," said Cynthia Cruder. "What we think is that sad and self-focused people are feeling pretty bad about themselves, and one way to deal with this is buying material goods." In a perfect situation, when you know you are sad, you should avoid making decisions and spending money. Sounds simple? Sadly, it is not. Most people don't even know they're sad, the study shows, and they are not aware that their feelings influence their decisions. What to do? The study showed that those who watched a tragedy were more likely to spend three times more money for a simple bottle of water than those who watched a comedy. The solution: well, for starters, don't go shopping! If you can't help it, it is probably better to see a doctor.
Answer: go to hospital and get checked out by a doctor

Answer:
When you can't help shopping after feeling sad, you'd better _ .