How to Write an AbstractThe rules for writing an abstract (摘要) are almost the same to those for writing the summary of an investigation report. In an abstract you make an outline of the problem and the purpose of your investigation, mention very briefly how you conducted the investigation or tests, describe your main findings, and make the conclusions. All these must be done in as few words as possible: ideally, your abstract will be about 125 words long and never more than 250 words.From the abstract, readers must be able to decide whether the information you provide in the scientific paper or report is particularly interesting to them and whether they should read further. Because a scientific paper is written for readers who generally are familiar with your technical or scientific discipline (学科), you may use technical terminology (术语) in the abstract. The abstract should be written last, when the Whole paper has been written, so that you can make an abstract of the brief details you need from what you have already written. Why can you use technical terminology in the abstract Because our readers are usually()our scientific discipline.
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I’ve got my performance (appraise)()this month with my manager.
Psychology is the study of the mind and mental activities. For example, psychologists are interested in why some things make you sad, but others make you happy. They want to know why some people are shy, but others are quite talkative. They also want to know why people do the things that they do. They test intelligence.Psychologists deal with the minds and behavior of people. Your mind consists of all your feelings, thoughts, and ideas. It is the result of one part of the brain called the cerebrum (大脑). Your behavior is the way you act or conduct yourself. Examples of behavior include shouting, crying, laughing and sleeping.Several people have been instrumental in the field of psychology. Wilhelm Wundt set up the first psychological laboratory in Leipzig, Germany, in 1879. Ivan Pavlov, a Russian, is noted for his experiments with dogs in which he studied their reflexes (反射作用) and reactions. Around 1900, Sigmund Freud stated his theory that people try to repress any memo- ties or thoughts that they believed were not good.Psychologists should not be confused with psychiatrists. Psychiatrists deal only with mental illness. They are medical doctors who treat people. The cerebrum controls()
A. the mind
B. the body
C. the whole brain
D. the field of psychology
It’s no use (quarrel)()with them.
阅读以下文字,完成下列问题。 鲸鱼不同于其他鱼类,是温血动物,从冰天雪地的南北极到酷热的赤道都可以看到鲸鱼的踪迹,无论是在什么样的环境下,鲸鱼的体温均保持在36摄氏度左右,常在极圈活动的鲸鱼会具有局部异温功能。 像鲸鱼、海豹和海豚这些大部分时间或一直都呆在海里的哺乳动物,用特殊的高级脂肪“外衣”保持自己的体温。但对于那些必须通过潜水进行捕食的动物来说,光有皮毛保护是不够的,因为厚重毛发里的空气会被极强的水压挤出来,皮毛的保温功能会大大降低。而北冰洋和南极周围的海洋深水水温可以降到零下40摄氏度,没有其他的保暖措施显然不行。鲸鱼和其他温血动物最大的不同点在于,当其活动环境的温度较低时,水有相当大的比热及传热能力,因此温度变化很快,鲸鱼无法以聚集、筑巢等方式维持体温,于是演化出超厚的皮下脂肪。过去曾记录到鲸鱼脂肪厚度最高达50厘米。 鲸脂是一层包裹整个身体的厚重脂肪“外衣”,重量可以达到体重的一半。这层脂肪含有细细的血管组织,除帮助保持体温,还为很多需要长途跋涉进行繁殖和觅食的海洋动物提供了重要能量储备。除此之外,这层脂肪还可以帮助快速游动的动物将身体塑造成流线型,减少在水中游动时所消耗的能量,同时提高速度。动物栖身的海水温度越低,脂肪也就越厚,鲸脂是通过吸食母体乳液获得的,举例来说,一只灰鲸幼仔每天要喝掉30加仑乳液。但这么厚的皮下脂肪还是不能完全阻挡体温外流,因此鲸鱼还需要摄取大量食物,以维持体温。鲸鱼的前鳍、尾鳍、背鳍并无鲸脂的分布,当鲸鱼潜到阳光照射不到的深海,或是南、北极时,鲸鱼的鱼鳍难道不会冻到无法活动吗对此,鲸鱼鳍上的动脉分为无数平行的小动脉,每条小动脉周围又被许多纵行的静脉血管包围,形成一个个血管束,利用动脉与静脉的紧密接触减少热能的散失,这点和企鹅脚不怕冷的道理是一样的。 这个特别的系统,主要控制鲸鳍末端有可能散失的热量,继而保持体温,但当鲸鱼因为活动而体热增加时,这个机制就会自行关闭,动脉血将一直保持着原有的温度到达鳍肢,并把过多的热量散发出去,中途就不再把一部分热量传递给静脉。 此外,鲸鱼还会通过血管的收缩有效维持体温。当鲸鱼潜入深海时,周围温度降低,鲸鱼体表的血管会收缩,将血液集中送往脑部、心脏、肝、肾等内脏器官,从而维持内部体温;相反,当水温上升时,体表的血管便会扩张,加速散热。 根据本文,如果鲸鱼体表血管出现扩张,最可能是因为( )。
A. 鲸鱼内脏器官的血液量突然增加
B. 鲸鱼的鲸脂超过体重一半
C. 鲸鱼突然增加了其活动量
D. 鲸鱼所处的环境温度较高