尽管人为什么要睡觉这一头号题我们尚未弄清楚,但毫无疑问,人需要睡觉,其他动物也是如此。醒与睡的交替模式是与我们的习惯和感官密切相关的。动物靠视力寻找食物、栖息地和庇护,它们与人一样白天的大部分时间活动,晚上睡觉。为保持身体健康,一个人所需的睡眠时间因年龄不同而大不相同。学龄前儿童通常需要10~12个小时的睡眠时间,中小学生9~11个小时,成年人7~9个小时。成年人随着日益变老所需睡眠时间似乎也逐渐减少。睡眠时间也随种族不同而不同。据说,日本人,包括儿童和成年人,睡眠时间比欧洲人少。但这种不同也许是由于生活习惯而不是由于种族的原因造成的。
Valentine’s Day is a festival of romance and affection. The holiday is an interesting combination of pagan (异教徒的) and Christian influences. Some of the day’s customs probably came from an ancient Roman holiday caned Lupercalia, Which honored Juno (wife of Jupiter, the goddess of women, marriage, and childbirth) and Pan (the God of nature). During the Lupercalia festival, young women dropped poems bearing their names into a large vase. Each young man picked a name from the vase to find his sweetheart for that year. During the Middle Ages, church leaders wanted to relate this pagan holiday to Christianity, so they renamed it after a Christian saint and moved the holiday from February 15 to February 14, the feast day of St. Valentine. St. Valentine was a third-century Christian martyr, a young man who was imprisoned in Rome for refusing to worship pagan gods. According to legend, before Valentine was beheaded on February 14, he restored the eyesight of his jailer’s blind daughter. Then he sent her a farewell letter signed, "From your Valentine". This phrase is now a common expression of affection that appears on many of the holiday greeting cards. Perhaps another reason that February 14 was picked as a holiday for lovers was that the ancient Romans believed that birds began to mate on this date. In modern times, early in February of each year, card shops, drugstores, and department stores begin displaying a wide variety of greeting cards called valentines. Most of them are illustrated with the symbolic red heart, which stands for love. Many also show a picture of Cupid with his bow and arrow. Some valentines are very fancy--decorated with paper lace, scented satin, feathers, ribbons, or bows. Some contain affectionate verses, while others simply say, "Be my Valentine". There are special Valentines for various family members, sweet hearts, and friends. People sometimes send anonymous valentines to the persons whom they are in secret love with. On that day, children usually buy packages of small, inexpensive valentines to give to classmates and teachers. Sweet-hearts and married couples may exchange more expensive cards, along with small gifts. Men often give red roses or chocolates wrapped up beautifully in red, heart-shaped boxes to their girlfriends or wives. All the following statements about Valentine’s Day are true except ______.
A. Valentine’s Day is only celebrated by adults
B. Valentine’s Day is a religious as well as a secular (俗世的) holiday
C. the customs of Valentine can be traced far back to an ancient Roman holiday
D. it’s possible for someone to receive a gift on this particular day without knowing its sender
Valentine’s Day is a festival of romance and affection. The holiday is an interesting combination of pagan (异教徒的) and Christian influences. Some of the day’s customs probably came from an ancient Roman holiday caned Lupercalia, Which honored Juno (wife of Jupiter, the goddess of women, marriage, and childbirth) and Pan (the God of nature). During the Lupercalia festival, young women dropped poems bearing their names into a large vase. Each young man picked a name from the vase to find his sweetheart for that year. During the Middle Ages, church leaders wanted to relate this pagan holiday to Christianity, so they renamed it after a Christian saint and moved the holiday from February 15 to February 14, the feast day of St. Valentine. St. Valentine was a third-century Christian martyr, a young man who was imprisoned in Rome for refusing to worship pagan gods. According to legend, before Valentine was beheaded on February 14, he restored the eyesight of his jailer’s blind daughter. Then he sent her a farewell letter signed, "From your Valentine". This phrase is now a common expression of affection that appears on many of the holiday greeting cards. Perhaps another reason that February 14 was picked as a holiday for lovers was that the ancient Romans believed that birds began to mate on this date. In modern times, early in February of each year, card shops, drugstores, and department stores begin displaying a wide variety of greeting cards called valentines. Most of them are illustrated with the symbolic red heart, which stands for love. Many also show a picture of Cupid with his bow and arrow. Some valentines are very fancy--decorated with paper lace, scented satin, feathers, ribbons, or bows. Some contain affectionate verses, while others simply say, "Be my Valentine". There are special Valentines for various family members, sweet hearts, and friends. People sometimes send anonymous valentines to the persons whom they are in secret love with. On that day, children usually buy packages of small, inexpensive valentines to give to classmates and teachers. Sweet-hearts and married couples may exchange more expensive cards, along with small gifts. Men often give red roses or chocolates wrapped up beautifully in red, heart-shaped boxes to their girlfriends or wives. What are the most popular Valentine gifts
A. Flowers.
B. Candy.
C. Valentines.
D. All of the abov
If those "mad moments"--when you can’t remember what your friend has told you or where you left your keys--are becoming more frequent, mental exercises and a healthy brain diet may help. Just as bodies require more maintenance with the passing years, so do brains, which scientists now know show signs of aging as early as the 20s and 30s. "Brain aging starts at a very young age, younger than any of us had imagined and these processes continue gradually over the years," said Dr. Gary Small, the director of the Center on Aging at the University of California, Los Angeles. ’Tin convinced that it is never too early to get started on a mental or brain-fitness program," he added. In his book, The Memory Bible, the 51-year-old neuroscientist (神经学家) lists what he refers to as the 10 suggestions for keeping the brain young. They include training memory, building skills, reducing stress, mental exercises, brain food and a healthy lifestyle. "Misplacing your keys a couple of times don’t mean you should start labeling your cabinets. Memory loss is not an inevitable consequence of aging. Our brains can fight back," he said. Small provides the weapons for a full-scale attack. Simple memory tests give an indication of what you are up against and tools such as "look" and "connect" are designed to make sure that important things such as names and dates are never forgotten. "So if you wanted to learn names and faces, for example, you meet Mrs. Beatty and you notice a distinguishing facial feature, maybe a high eyebrow," said Small. "You associate the first thing that comes to your mind. I think of the actor Warren Beatty, so I create a mental picture of Warren Beatty kissing her brow." Small admits it may sound a bit strange but he says it works. "Mental exercises could be anything from doing crossword puzzles and writing with your left hand if you are right handed or learning a language. It could be anything that is fun that people enjoy doing," he added. In this passage, the author mainly tells us ______
A. everyone has bad memories sometimes no matter how old he is
B. we can prevent our mind from aging with various methods
C. brain aging starts at the time when we are in the 20s and 30s
D. memory loss is not the sign that we are getting old