Sleep is essential for a person's health and well-being, yet millions of people do not get enough of it. Sleep needs vary from $\fbox{1}$. Healthy adults generally require an average of 16 hours' wakefulness and 8 hours' sleep a day. However, some individuals are able to function without feeling sleepy after as little as 6 hours' sleep. Others, on the other hand, cannot perform at their peak unless they get 10 hours' sleep. Contrary to common myth, the need for sleep does not decline with age once people enter adulthood. What often declines as adults get older, however, is the ability to sleep for 6 to 8 hours at one time.

According to surveys done by the National Sleep Foundation, 60% of adult Americans have sleep problems one or more nights a week, most of which go undiagnosed and untreated. In addition, more than 40% of adults experience daytime sleepiness $\fbox{2}$ to interfere with their daily activities at least a few days a month, with 20% saying they feel sleepy a few days each week. The survey results also show that over 2 in 3 children experience sleep problems one night or more a week.

Some of the first signs of sleep deprivation are irritability, moodiness, and an inability to suppress emotions. If a sleep-deprived person is not able to switch back to normal sleep patterns after the initial signs appear, he or she may then start to show indifference, slowed speech and weakened emotional responses, memory loss, and an inability to be novel or to multitask. He or she will also fall into microsleeps (short periods of sleep lasting only a few seconds), which cause attention gaps. Microsleeps are extremely dangerous when they occur in situations that demand constant alertness, such as when driving a motor vehicle or $\fbox{3}$. People who experience microsleeps usually remain unaware of them, instead believing themselves to have been awake the whole time, or to have temporarily lost focus.

Stress is the number one cause of short-term sleeping difficulties, sleep experts say. Common triggers include school-or job-related pressures, a family or marriage problem, and $\fbox{4}$. Usually the sleep problem disappears when the stressful situation passes. However, if short-term sleep problems are not managed properly from the beginning, they can persist long after the original stress has passed.

Consuming alcohol can also disrupt sleep, as can drinking beverages containing caffeine in the late afternoon or evening, exercising hard close to bedtime, following an irregular daily schedule, and doing mentally intense activities right before getting into bed.

Environmental factors such as sleeping in a room that is too hot or cold, too noisy, or too brightly lit can be a barrier to sound sleep, as can interruptions from children or other family members. Sleeping in the same room as someone else can also adversely affect your sleep, especially if that person goes to bed and/or gets up at different times from you, moves around a lot when asleep, snores, cannot fall or stay asleep, or has other sleep problems.

1. In A to D below, select the option that best completes each sentence to reflect the contents of the passage. In E, select the best answer to the question.
   • A. As adults get older, they tend to
     • a. need more sleep.
     • b. need less sleep.
     • c. find it harder to stay asleep all night.
     • d. find it easier to stay asleep all night.
   • B. The National Sleep Foundation survey results indicate that
     • a. children suffer sleep problems at a higher rate than adults.
     • b. adults suffer sleep problems at a higher rate than children.
     • c. a majority of those with sleep problems are receiving appropriate therapy.
     • d. a majority of those with sleep problems experience daytime sleepiness a few days each week.
   • C. The secondary signs of sleep deprivation
     • a. are in some respects the reverse of the initial signs.
     • b. are more intense versions of the first signs.
     • c. include a tendency to be quick to get angry.
     • d. include a heightened ability to recall past events.
   • D. Short-term sleeping difficulties caused by stress
     • a. invariably disappear once the stressful situation passes.
     • b. do not necessarily cease after the direct cause is resolved.
     • c. only persist for as long as the person experiencing them is under stress.
     • d. are the number one cause of chronic sleep disorders.
   • E. Which of the following measures does the passage not suggest will help combat common sleep problems?
     • a. Sleeping alone.
     • b. Minimizing excessive heat or cold in your bedroom.
     • c. Keeping your bedroom dark when you sleep.
     • d. Avoiding heavy meals before bedtime.
2. Select the best option to fill each of the blank spaces marked $\fbox{1}$ and $\fbox{2}$.
   • $\fbox{1}$
     • a. each other
     • b. one another
     • c. person to person
     • d. people to people
   • $\fbox{2}$
     • a. enough severe
     • b. severe enough
     • c. sufficient severe
     • d. severe sufficient
3. Give another example of a situation demanding constant alertness that could be used to fill the blank space marked $\fbox{3}$. Answer in English, using at least three words.
4. Suggest another common trigger that could be used to fill the blank space marked $\fbox{4}$. Answer in English, using at least three words.
5. The fifth paragraph of the passage lists five activities that can lead to sleep problems. On the basis of the information given in this paragraph, we could make a list of things people can do to promote better sleep. The first one is to avoid drinking alcohol. What are the other four? Answer in Japanese.