Passage 2 Insomnia is the inability to get high-quality sleep, which may cause fatigue during the
day or even concentration problems. By trying one of the many strategies below, you’ll be
taking the first step toward getting some much-needed rest.
Learning to be physically and mentally relaxed before going to bed will help you fall
asleep more quickly. Some people find that taking a bath slows them down from the activity
of the day. Other people benefit most from muscle relaxation techniques. Meditating with a
focus on breathing, handling stress in a positive way, and exercising regularly may also
induce a good night sleep.
Some foods can also help you sleep well. Foods such as chicken, milk, cheese, and beans
contain tryptophan, a chemical that is converted in the brain to serotonin, which promotes
relaxation and sleepiness. If you include foods high in tryptophan in your daily diet and
incorporate some of the sleep-inducing activities into your life, the chances are good that you
will achieve a pattern of restful, soothing sleep.
【題組】39. What does which in paragraph 3 refer to?
(A) tryptophan
(B) brain
(C) chemical
(D) serotonin
(E) sleepiness