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.

Let me give you an example: Article: Homework can put you in a badmood , and that might actually be a good thing. Researchers from the University of Plymouth in England doubted whether mood might affect the way kids learn. To find out the answer, they did two experiments with children. The first experiment tested 30 kids. Someshapes were hidden inside a different, larger picture. The kids had to find the small shapes while sitting in a room with either cheerful or sad music playing in the background. To test their mood, the scientists asked the kids to point to one of five faces, from happy to sad. Children who listened to cheerful music tended to point to the smiley faces while the others pointed to the unhappy ones. The researchers found that sad kids took at least a second less to find the small shapes. They also found an average of three or four more shapes. In the second experiment, 61 children watched one of two scenes from a film. One scene was happy, and the other was sad. Just like in the first experiment, kids who saw the sad scene acted better compared to the others. The researchers guessed that feeling down makes people more likely to focus on a problem or difficult situation. Not all scientists agree with them, however. Other studies argued that maybe, that cheerful music in the first experiment distracted kids from finding shapes. While scientists work on finding out the answers, it still might be wise to choose when to do your tasks according to your mood. After eating a delicious ice cream, for example, write an essay.
Answer: whether mood affects their learning ability
The answer to this example can be: Researchers did experiments on kids in order to find out _ .
Here is why: It is clearly mentioned in the article that to the check effect of mood on children is the main purpose of the experiment.

OK. solve this:
Article: We do not know when man first began to use salt, but we do know that it has been used in many different ways throughout history. Historical evidence shows, for example, that people who lived over 3,000 years ago ate salted fish. Thousands of years ago in Egypt, salt was used to preserve the dead. Stealing salt was considered a major crime during some periods of history. In the eighteenth century, for example, if a person was caught stealing salt, he could be put in prison and his ears could be cut off. In the Roman Empire, one of the most important roads was the one that carried salt from the salt mines to Rome. Guards were stationed along the route to protect against salt thieves, and they received their pay in salt, thus bringing the English word, salary. Any guard who fell asleep while on duty was thought to be "not worth his salt", and as a result he would get a little less salt on his next payday. The expression, "not worth his salt", is still used today in English. In the modern world salt has many uses beyond the dining table. It is used in making glass and airplane parts, in the growing of crops, and in the killing of weeds . It is also used to make water soft, to melt ice on roads and highways, to make soap, and to fix colors in cloth. Salt can be got in various ways besides being taken from mines underground. Salt water from the ocean, salt water lakes or small seas can be used to make salt. Yet, no matter where it comes from, salt will continue to play an important role in the lives of people everywhere.
Answer: punishing thieves
Answer:
According to the text, salt can be used in the following EXCEPT _ .