D
Willi around 100 students scheduled to be in that 9 am Monday morning lecture, it is no surprise that almost 20 people actually make it to the class and only 10 of them arc still awake after the first IS minutes; it is not even a surprise that most of them are still in their pyjamas (睡衣). Obviously, students are terrible at adjusting their sleep cycles to their daily schedule.
All human beings possess a body clock. Along with other alerting (警报) systems, this governs the sleep/wake cycle and is therefore one of the main processes which govern sleep behaviour. Typically, the preferred sleep/wake cycle is delayed in adolescents, which leads to many students not feeling sleepy until much later in the evenings. This typical sleep pattern is usually referred to as the "night owl" schedule of
This is opposed to the "early bird" schedule, and is a kind of disorder where the individual tends to stay up much past midnight. Such a person has great difficulty in waking up in the mornings. Research suggests that night owls feel most alert and function best in the evenings and at night. Research findings have shown that about 20 percent of people can be classified as "night owls" and only 10 percent can be classified as "early birds" - the other 70 percent are in the middle. Although this is clearly not true for all students, for the ones who are true night owls this gives them an excellent excuse for missing their lectures which unfortunately fall before midday.

43. What docs the author stress in Paragraph I?
A. Many students are absent from class.
B. Students are very tired on Monday mornings.
C. Students do not adjust their sleep patterns well.
D. Students are not well prepared for class on Mondays.

44. Which of the following is true according to Paragraph 2?
A. Most students prefer to get up late in the morning.
B. Students don't sleep well because of alerting systems.
C. One's body clock governs the sleep/wake cycle independently.
D. Adolescents' delayed sleep/wake cycle isn't the preferred pattern.

45. Which of the following is closest in meaning to the underlined word "classified"? 
A. Criticised.B. Grouped.C. Organised.D. Named.

46. What docs the text mainly talk about?
A. Functions of the body clock.B. The "night owl" phenomenon.
C. Human beings' sleep behaviour.D. The school schedule of "early birds".

E
Women are friendly. But men are more competitive. Why? Researchers have found it's all down to the hormone oxytocin (荷尔蒙催生素). Although known as the love hormone, it affects the sexes differently.
"Women tend to be social in their behavior. They often share with others. But men lend to be competitive. They are trying to improve their social status," said Professor Ryan.
Generally, people believe that the hormone oxytocin is let out in our body in various social situations and
our body creates a large amount of it during positive social interactions (互动) such as falling in love or giving birth.
But in a previous experiment Professor Ryan found that the hormone is also let out in our body during negative social interactions such as envy.
Further researches showed that in men the hormone oxytocin improves the ability to recognize competitive relationships, but in women it raises the ability to recognize friendship. Professor Ryan's recent experiment used 62 men and women aged 20 to 37. Half of the participants（参与者）received oxytocin. The other half received placebo (安慰剂).
After a week, the two groups switched with participants. They went tlirough the same procedure with the other material.
Following each treatment, they were shown some video pictures with different social interactions. Then they were asked to analyze the relationships by answering some questions. The questions were about telling friendship from competition. And their answers should be based on gestures, body language and facial expressions.