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.
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
Example solution: Researchers did experiments on kids in order to find out _ .
Example explanation: It is clearly mentioned in the article that to the check effect of mood on children is the main purpose of the experiment.

Problem: Article: A few years ago, an Englishman called Roy Jones went on holiday to a small seaside town in the west of England. He was swimming in the sea one day when, as he opened his mouth, his false teeth fell out and floated away. The following year, Mr. Jones returned to the same town. As he was having dinner in a local cafe one evening, he mentioned the story of his lost teeth to the manager. The manager looked surprised. He explained that he had found a set of false teeth on the beach last month. Then he asked Roy Jones if he wanted to try them on. "OK", said Mr. Jones. "I suppose it won't do any harm." When the manager brought him the teeth, Mr. Jones put them into his mouth, and laughed and laughed. They were his. In 1987, an American couple called Jane and Robert Bentley went for a picnic on a beach in California. When they returned home, Mrs. Bentley realized that she had lost her wedding ring. It wasn't a lot of money but it was valuable to Jane Bentley. The Bentleys drove straight back to the beach, and searched for the ring for three hours, but could not find it. A few months later, Mr. Bentley went fishing off the same beach. As he pulled a large crab out of the sea, he noticed that there was something attached to one of its claws. It was his wife's wedding ring! At the end of the 19thcentury, a young woman called Rose Harcourt was on her honeymoon in Barmouth, North Wales, when she lost a gold bracelet her husband had given her as a wedding gift. Feeling very upset, she went straight to the police stations and asked if anyone had found her bracelet. Unfortunately, no one had. Twenty-five years later, the Harcourts returned to Barmouth _ They were sitting on the beach one day when Mrs. Harcourt noticed something gold in the sand by the edge of the sea. She walked down to see what it was, and discovered her gold bracelet that had been missing for 25 years.
Answer: when he opened his mouth as he was swimming
Solution: Roy Jones lost his false teeth _ .