Exercise 4 (200606新)
Do you wake up every day feeling too tired, or even upset? If so, then a new alarm clock could be just for you.
The clock, called SleepSmart, measures your sleep cycle, and waits   67   you to be in your lightest phase of sleep   68   rousing you. Its makers say that should   69   you wake up feeling refreshed every morning.
As you sleep you pass   70   a sequence of sleep states—light sleep, deep sleep and REM （rapid eye movement）sleep—that   71   approximately every 90 minutes. The point in that cycle at which you wake can   72   how you feel later, and may   73   have a greater impact than how much or little you have slept. Being roused during a light phase   74   you are more likely to wake up energetic.
SleepSmart   75   the distinct pattern of brain waves   76   during each phase of sleep, via a headband equipped   77   electrodes（电极）and a microprocessor. This measures the electrical activity of the wearer’s brain, in much the   78   way as some machines used for medical and research   79    and communicates wirelessly with a clock unit near the bed. You   80   the clock with the latest time at    81   you want to be wakened, and it   82   duly（适时地） wakes you during the last light sleep phase before that.
The　　83　　was invented by a group of students at Brown University in Rhode Island   84 a friend complained of waking up tired and performing poorly on a test. “   85   sleep–deprived people ourselves, we started thinking of   86   to do about it,” says Eric Shashoua, a recent college graduate and now chief executive officer of Axon Sleep Research Laboratories, a company created by the students to develop their idea.
67. A）beside        B）near           C）for            D）around
68. A）upon          B）before         C）towards        D）till
69. A）ensure         B）assure         C）require         D）request
70. A）through        B）into           C）about          D）on
71. A）reveals        B）reverses       C）resumes        D）repeats
72. A）effect         B）affect          C）reflect        D）perfect
73. A）already        B）ever