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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.

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

New input: Article: For most South Africans, Nelson Mandela is the father of their nation - many even called him "Tata", a local word for father. It was sometimes forgotten that he was also a real father of six, grandfather of 18, great-grandfather of eight, and husband to three women. He earned a place in history just like another father of a nation, Mahatma Gandhi. But there was a fundamental difference between these beloved men. While Gandhi was thought to be a depressed family man, Mandela was a strong and loving family man. Even so, Mandela and his family paid dearly for his devotion to his country's freedom. Mandela himself offered a glimpse into his personal war. "To be the father of a nation is a great honor, but to be the father of a family is a greater joy. _ " he said in April 1992, announcing his separation from Winnie. In 1944, Nelson Mandela married Evelyn. "I could not give up my life in the struggle," Mandela explained in his autobiography , Long Walk to Freedom, "and she (Evelyn) could not live with my devotion to something other than herself and her family... I never lost my admiration for her, but in the end we could not make our marriage work." They divorced in 1958. When Evelyn died in 2004, Mandela stood at her graveside with his third wife, Graca. Winnie also attended the funeral. Mandela married Winnie in 1958. But Winnie bore the hardship of life as Mandela, enduring her husband's 27-year imprisonment. From prison, Mandela wrote some of the greatest love letters to Winnie. "I dust it (your photo) carefully every morning - I even touch your nose with mine to regain the electric current that used to run through my blood whenever I did so." For many South Africans, it was the end of a fairytale love story when their separation was made public in 1992. "Tensions" had arisen and they had agreed on a separation. The hurt in his words was clear: "Perhaps I was blinded to certain things because of the pain I felt for not being able to play my role as a husband to my wife and a father to my children." "Unstable personal lives seemed freedom fighters' destiny ," he said. "When your life is the struggle, as mine was, there is little room left for family. That has always been my greatest regret, and the most painful aspect of the choice I made." The couple divorced in 1996.
Answer: Evelyn
Solution:
The first wife of Nelson Mandela is _ .