NewYear's Day is _______．

1. A.
   August 1
2. B.
   February 1
3. C.
   January1
4. D.
   July 1

Do you know why you sleep? You may think it’s because you’re tired. Or perhaps you’ve been told sleep is good for you. Yet no one knows exactly why or how people sleep.
Until the early 1950s, most scientists thought the body and brain rested during sleep. Then a scientist watched people sleep. He noticed that during periods of between 5 and 30 minutes each, sleepers’ eyes made rapid movements, as if they were watching something. He called these periods REM sleep, for Rapid Eye Movement. Periods when sleepers’ eyes did not move he called non-REM sleep.
Whenever the scientist woke people during REM sleep, they were having vivid dreams. Measurements showed that sleepers’ pulses（脉搏）went up quickly during REM sleep. Their breathing, heartbeat, and the blood going to the brain also increased. Far from being a time of rest, REM sleep is a time when the body is hard at work. Scientists still don’t know the reason for this. Some believe REM sleep makes learning easier. Babies spend a lot of time in REM sleep. Because of this, some scientists believe that REM sleep helps the brain grow. Others think REM sleep is a time for the brain to empty the day’s garbage.
One thing all the scientists agree on is that sleep is necessary. Without enough sleep, people make mistakes. Most major car accidents happen during the early morning hours, when people are sleepiest.
【小题1】During REM sleep, a person’s breathing and heartbeat ________.

Not long ago, I opened an interesting e-mail from Jennifer, a friend of mine. “I’ve realized I want to be around people who make me happy,” she wrote, “I’ve been seeing how I feel after communicating with different people and making a mental list of who I feel good about. And you’re on my list.”
Then she invited me — and 11 other women— to a “Movie Night” to be held every six weeks at her house. We’d chat, eat, and watch feel-good movies. She made it clear in her invitation that there was no stress to show up to all or any movie nights. Wonderful! I e-mailed her back immediately. I was in.
Later, Jennifer told me she had some puzzled reactions to her invitation. Though all the women were willing to join, some said they didn’t see themselves as cheerful people. “I’ve told them they didn’t have to be cheerful around me all the time. I invited them because they made me feel happy,” she says.
Research shows that gatherings such as Jennifer’s make sense. In a US study, researchers measured(测量) the happiness of 4739 people at regular intervals (间隔) over 20 years. The study found that a person’s happiness depends on(取决于) the happiness of people they connect with. Amazingly, it also found that happiness spreads not only between direct friends, but also among friends of your friends’ friends! And those good feelings seem to be the most contagious (传染性的) among friends of the same sex.
“People with more supportive friends are less likely to develop sadness,” says Dr Toupey Luft, a psychologist in Penticyon, British Columbia. “Though you can’t choose your family or workmates, you do have control over friendships.” With a little effort, you can add more positive(乐观的) relationships to your social circle. Here’s how…
【小题1】How many people did Jennifer invite?