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: Nine years ago, after Leo had died, people said to me. "I never knew he was your stepfather." You see, I never called him that. At first, he was no one special in my life. Then he became my friend. In time, I felt he was also my father. Leo married my mother when I was eleven. Two years later we moved into a house in a new suburban development, where we put down roots. At first our lawn was just a mud with wild grass, but Leo saw bright possibilities. "We'll plant trees there to give us shade as well as some flowers," he said. And just these little touches made our house different from all the others. More important, a real family was forming. Leo was becoming a full-time parent, and I was learning what it meant to have a father. Weekday mornings when the weather was bad, Leo often drove me to school. Having a father drop you off may have been something my classmates took for granted, but I always thought it was wonderful. Saturday mornings, we went to the hardware shop, then stepped into the five-and-ten, buying a sports magazine or something else. Some people might think that doing shopping together is nothing special, but I, who had ever before spent my childhood watching other families do their everyday activities, experienced them now with extreme delight. Looking back, I realized that Leo gave me what I needed most--the experience of doing ordinary things together as a family. Soon after we moved to the suburbs, one of our new neighbors introduced herself to me. She had already met my mother and Leo. "You know," she said, "you look just like your father." I knew she was just making conversation--but even so... "Thank you", I said. Why tell her anything different?
Answer: to show his pride to have a good stepfather
Answer:
The writer's purpose in writing this passage is _ .