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: If you were given a chance to choose your favorite life metaphor , what would it be? Do you agree with Forrest Gump's mother that life is "a box of chocolates" because "you never know what you're going to get"? Or do you prefer the phrase from the 1930's song that "life is just a bowl of cherries "? Though simply stated, each conveys a very different view. A "box" implies mystery, because we don't know what is in a closed box. Meanwhile, a "bowl" of cherries is completely in view. For many centuries, the metaphor of life that probably burst into most people's mind was the one suggested by Shakespeare: "All of life is a stage..." On that stage, we take seven roles. More recently, psychologist Erik Erikson took up the idea of life as a stage. Erikson regarded development as a "powerful unfolding" in which we are driven from one stage to the next as our bodies, minds, and social roles develop. Stage metaphors fit with many of our common-sense ideas about change, but the problem with the stage metaphor is that it isn't particularly accurate. None of the studies that try to clarify the universality of adult life stages actually studied people as they developed over time. All of them were based on performances of their samples at one point in time. People's actual lives don't fit into these stage metaphors. They don't automatically transform when people reach a certain age. Instead, people's real lives are messy, unpredictable, and full of surprises. Today, I'd like to focus on an even longer study, an 80-year study which is the subject of a recent book by Howard Friedman and Leslie Martin. Their final chapter summarizes the "many changes of healthy and unhealthy pathways" that their participants took over the course of their lives. As I too discovered in my research, the pathway provides a perfect metaphor of human development. We don't all go down the same road marked with the same signposts based on age. People travel through diverse routes as they track the years of adulthood. Friedman and Martin use health and long life as their measure; I've used sense of achievement. In both cases, we are in perfect agreement in evaluating development not according to age but "the key features of life". The paths that Friedman and Martin describe seize the changes that characterize people as they age. Some examples are "The High Road" (reliable, full of plans); "Not Easy Street" (exposed to high stress throughout life), "Catastrophe Lane" (a downwardly twisty life); "Happy Trails to You" (cheerful, sociable), "The Road to Resilience" (able to handle stress with a strong will). Though I haven't yet been able to follow my participants for 80 years, I too saw some of these pathways among my samples: "The Minding Way" , "The Downward Slope" , "The Straight and Narrow Path" , and "The Successful Trail". The pathway metaphor gives you hope for changing the direction of your life if you are unhappy with it so far. You can't stop the clock from ticking the minutes between one birthday and the next, but you can adjust the road that you're on by changing yourself, your situation, or both.
Answer: hasn't enough stages to clarify life changes
Answer:
According to the passage, the "stage metaphor" _ .