Given the task definition, example input & output, solve the new input case.
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
Output: Researchers did experiments on kids in order to find out _ .
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 case for you: Article: There was good news last week for people who struggle to get eight hours of sleep a night: they may not need so much shut-eye after all. Researchers from UCLA and elsewhere looked at sleep habits of remote hunter-gatherers in Tanzania, Namibia and Bolivia -- groups with pre-industrial lifestyles whose sleep patterns are believed to reflect those of ancient humans. The researchers found that, on average, members of each group sleep a bit less than six and a half hours a night. The study, published in the academic journalCurrent Biology, indicates that "natural" sleep is less than eight hours a night and that modern society's numerous electronic distractions aren't necessarily to blame for people getting just six or seven hours of sleep. "The story that often gets out is that if you sleep for less than seven hours, you're going to die early," he told me. "That's not true." Yet Americans are addicted to getting more sleep -- and on turning to medical shortcuts to help them. According to the Centers for Disease Control, as many as 70 million U.S. adults suffer from sleep disorders or sleeplessness. Only a third of Americans get the government's recommended seven to nine hours of sleep a night. About 9 million American adults use sleeping pills to help get a good night's rest, the CDC found. Siegel said the number of people relying on medicines "has gone up rather rapidly since then." Industry consulting firm GlobalData estimates that worldwide sales for sleeplessness medicines will run about $1.4 billion next year and reach $1.8 billion by 2023, recovering from lower sales in recent years because of cheaper generics hitting the market. Dr. Roy Artal, a sleep specialist in West Los Angeles, said it's understandable that busy people in today's go-go world would turn to medicines to speed up the sleep process. But all they're doing is building a reliance on powerful drugs for relatively little improvement. "There's no magic pill that makes us sleep when we want and wake up when we want," Artal said. "The effects of sleeping pills tend to be _ ." He and other experts say the answer to sleeplessness isn't to be found in a pill bottle. It's in what's called "sleep hygiene ."
Answer: "natural" sleep may be less than eight hours a night
Output:
The research on sleep habits of remote hunter-gatherers in Tanzania, Namibia and Bolivia shows that _ .