阅读理解 Do you find getting up in the morning so difficult that it's painful? This might be called laziness, but Dr. Kleitman has a new explanation. He has proved that everyone has a daily energy cycle.
During the hours when you labor through your work you may say that you are "hot". That' s true. The time of day when you feel most energetic is when your cycle of your body temperature is at this peak. For some people the peak comes during the morning. For others it comes in the afternoon or evening. No one has discovered why this is so, but it leads to such familiar words as: " Get up, John! You'll be late for work again!" The possible explanation to the trouble is he is at his temperature-and-energy peak in the evening. Much family quarrelling ends when husbands and wives realize what these energy cycles mean, and which cycle each member of the family has.
You can' t change your energy cycle, but you can learn to make your life fit it better. Habit can help. Dr. Kleitman believes. Maybe you' re sleepy in the evening but feel you must stay up late anyway. Counteract your cycle to some extent by habitually staying up later than you want to. If your energy is low in the morning but you have an important job to do early in the day, rise before your usual hour. This won' t change your cycle, but you'll get up steam and work better at your low point.
Get off to a slow start, which saves your energy. Get up with a leisurely yawn and stretch. Sit on the edge of the bed a minute before putting your feet on the floor. Avoid the troublesome search for clean clothes by laying them out the night before. Whenever possible, do routine work in the afternoon and save tasks requiring more energy for your sharper hours.

单选题 16.Dr. Kleitman thinks that______.

A、 getting up late in the morning means laziness
B、 if your energy peak is in the evening, you might like getting up early
C、 people can do nothing about energy cycle
D、 spending some time yawning and stretching helps to keep you energetic

【正确答案】 D

【答案解析】由最后一段“Get off to a slow start，which saves your energy．Get up with a leisurely yawnand stretch．”可知。

单选题 17.According to the passage, family quarrels may result from______.

A、 the same energy cycle of family members
B、 unawareness of different energy cycles
C、 failing to get up early in the morning
D、 knowledge of energy cycles

【正确答案】 B

【答案解析】由第二段“Much family quarrelling ends when husbands and wives realize what these energycycles mean．and which cycle each member of the family has．”可知，家庭争吵是由于没有意识到成员之间不同的能量循环。

单选题 18.If you are used to getting up late in the morning, you are likely to be most energetic

A、 in the morning
B、 at noon
C、 in the afternoon
D、 in the evening

【正确答案】 D

【答案解析】从第二段的例子可看出，早上起床晚说明能量高峰在晚上。

单选题 19.What' s the likely relationship between energy cycle and body temperature?

A、 Energy cycle and body temperature are the same things.
B、 The higher your temperature is, the less energetic you are.
C、 The higher your temperature is, the more energetic you are.
D、 There is no direct relation between them.

【正确答案】 D

【答案解析】由第二段“The time of day when you feel most energetic is when your cycle of your bodytemperature is at this peak．”可知，精力最充沛时，体温也最高。

单选题 20.Which of the following statements is not true?

A、 One can change his energy cycle once he makes up his mind.
B、 We still don' t know why people have different energy cycles.
C、 Habit will help to make our life fit energy cycles better.
D、 If you rise earlier than usual, you will be more efficient at your low point in the morning.

【正确答案】 A

【答案解析】由第三段“You can’t change your energy cycle…”可知A错误。