Is sleep important to children？A new study says yes.

A new study published this week shows that children who do not get _____ sleep have less control over emotions and are less focused at school.

The National Sleep Foundation _____ 10 to 11 hours of shut-eye per night for children aged between 5 and 12. About 41 million American workers get less than six hours of sleep per night. Now health experts _____ that adults are passing their poor sleeping _____ down to their children.

Reut Gruber is a lead author of the new study. In the study，Gruber and other experts either added or reduced one hour of sleep for _____ children aged 7 to 11. They _____ the children over five nights. The _____ was to see if small changes in the amount of sleep could _____a child's behavior.

“The findings show that for children small changes can make a big _____，and that is why this is meaningful.”

Before the survey began, students were _______to sleep the same amount of hours as they ______ would. Their teachers were asked to ______ the children on thoughtfulness, touchiness and emotional reactions. After five nights of the kids' sleep change, the teachers were asked to take the survey again. ______ their original scores, those who slept one hour less had ______ behavior scores than those who were allowed to sleep an hour more.  Students with less sleep were more annoyed, frustrated and had more problems which need paying ______ to.  The children with more sleep showed ______ in these areas.

“______ less sleep leads to a drop in attention in class, children may ______ on learning and chances to be ______. If they are easily annoyed and frustrated because their bodies and brains are ______, they may not learn as much either,”says Gruber.

   We all know the keys to living longer：eating healthily，exercising daily，and avoiding bad lifestyle habits，but do you know that practicing these simple steps when you’re 50 and older can add more years to your life？

According to a new research conducted by Harvard University scientists，adults who follow five healthy habits which include never smoking，maintaining a body mass index（BMI）（体重指数）below 30，exercising for at least 30 minutes a day，drinking alcohol only reasonably，and following a well-balanced diet，can add a decade or more to their lifespan.

The study，published in the American Heart Association’s journal Circulation，suggests that men over age 50 who follow these five lifestyle habits can add up to 12 years to their lives while women who follow these healthy habits can add 14 years to their lifespan. While the method of living a longer and healthier life hasn’t changed much over the years，this new information regarding the benefits of working out and eating healthily later in life is a bit of a breakthrough in terms of how we look at aging.

Modern medicine often treats the elderly with a more reactive approach，focusing on discovering and creating medicines and therapies to combat（防止）life-threatening illnesses like cancer and especially heart disease. According to scientists who conducted this study，the focus should be on preventative（预防的）measures，making sure aging adults are adapting healthy habits before they reach a stage in life when health issues normally arise.

It is very important to put prevention through diet and lifestyle changes first. Heart disease and cancer are the leading causes of death in the United States，while heart disease in particular can arise because of certain lifestyle habits. One of those habits is smoking，which scientists said was the biggest determining factor in a person’s lifespan. Researchers found that there was a direct connection between an adult’s risk of early death and his lifestyle habits，with those following all five of the healthy habits enjoying significantly longer lives.

   Just like humans, birds rely on sound to communicate, too. Often, birds recognize their mates or young by sound rather than sight. Hungry young birds use begging calls to let their mothers know it is feeding time, and warning calls are other sounds given out frequently by the adults. In addition to all these regular calls, some male birds develop beautiful songs intended（打算）to attract the females.

A new study carried out by an American university shows that songbirds practice their songs even in their sleep. The research team discovered that the electrical brain activity of the birds that were asleep was similar to the brain activity produced when the birds were awake and singing. Clearly the bird stores a song after hearing it, then practices it later in its sleep. Scientists now believe the birds dream of songs to help them master the fine art of singing and that sleep plays a key role in the learning process！

It is commonly known that many songbirds learn to sing by listening to adult birds of the same species. If taught the song of an adult of another bird species, the chick grows up singing the new song and passes on the foreign song to its chicks. For instance, researchers carried out an experiment in which a male bullfinch（红腹灰雀）was raised by a female canary（金丝雀）. The bullfinch soon learned the canary's songs and when it was later mated to a female bullfinch, Mr. Bullfinch taught his children the canary's songs.

Early last year, a British survey of London's songbirds showed that the city's birds are losing their melodies. Birds could hardly hear one another over the traffic noise；as a result they had difficulty in learning songs and communicating with potential mates. And instead of copying the sweet notes of the adults, chicks were copying sounds, which they heard most often—namely car horns（喇叭）and mobile phones！