[单项选择]As mainstream chip production technology shifts from one generation to the next every three to five years, plants with new technology can make more powerful chips at lower costs, ______ plants with outdated equipment, which often cost billions of dollars to build, will be marginalized by the maker.
A. because
B. even though
C. while
D. since

[单项选择]People who work night shifts are constantly fighting against an “internal clock” in their bodies. Quite often the clock tells them to sleep when their job requires them to remain fully awake. It’s no wonder that more accidents happen during night shifts than at any other time. Light therapy(光照治疗法)with a bright light box can help night-shift workers adjust their internal clock. However, many doctors recommend careful planning to help improve sleep patterns For example, night-shift workers often find it difficult to sleep in the morning when they get off work because the body’s natural rhythm(节律)fights back, no matter how tired they are. Some experts recommend that night-shift workers schedule two smaller sleep periods-one in the morning after work, and another longer one in the afternoon, closer to when the body would naturally need to sleep. It’s also helpful to ask friends and family to cooperate by avoiding visits and phone calls during the time when you are sleeping.
Night-shift
A. have to pay on their internal clock
B. need to re-adjust their clock
C. fall asleep late at night
D. have to work at night

[填空题]People who work rotating night shifts appear to have a lower (47) of Parkinson’s disease, the results of a study published in the American Journal of Epidemiology. And (48) , an increased risk of developing this condition is linked to a longer average duration of sleep.
"Working rotating night shifts disrupts rhythms and may have a wide (49) of physiologic (理疗) effects on shift workers," Dr. Honglei Chen, of the National Institutes of Health, writes.
"In the (50) studies, some inference has been confirmed. Shift work has been (51) to higher risks of some chronic diseases, including certain types of cancers," they note, but any effect on the risk of developing Parkinson’s disease has not been (52) .
The researchers therefore (53) data from the U.S. Nurses’ Health Study, which enrolled 84, 794 female nurses, to see if there was an association between working rotating night shifts and Parkinso

[填空题]The two major shifts the U.S. population is undergoing are changes in geographic distribution and in______.

[单项选择]Questions 19～22A. Working night shifts to make money. B. Taking final examinations.
C. Visiting the United States. D. Consulting a tourist agent.

[填空题]früh

[单项选择]A. Working night shifts to make money. B. Taking final examinations.
C. Visiting the United States. D. Consulting a tourist agent.