概要（summary）是用自己的话写出文章的主要内容，是文章的浓缩，在内容上要与原文相符，语气上力求客观，行文上做到简洁，长短一般是原文的1/4或1/3。一篇文章的概要根据文章长度从一段到一页纸不等，一本书的概要则到两页左右。要写好一篇概要，概括能力是根本要求。首先要认真阅读原文，找出最基本的观点，然后运用恰当的衔接手段，用自己的话写成独立的篇章。所以概要写作的关键在于对原文的理解，要求作者能很好地区分出原文的主要观点、次要观点和细节，着重将与中心有关的要点用自己的话写出来，努力做到简洁、清晰、客观、完整。
概要的一个特点是简洁性（conciseness）。概要的目的就是将原文信息尽可能用简洁的话概括，以便让他人能在短时间内了解原文。概要的另一个特点是客观性（objectivity）。概要的宗旨就是客观反映原文，概要的作者在对原文理解的基础上对原文进行客观的浓缩，不附带任何个人观点，对于原文的评论更不能出现在概要里面。完整性（completeness）也是概要的一个特点。概要的简洁性与客观性都依赖于对原文所有信息主旨的把握，要反映原文的全貌，这样才能体现概要的客观性。原创性（originality）是概要的又一重要特点。概要的作者必须在理解原文全文的基础上，运用自己的语言组织文章、重现原文、不能照搬原文中的文字。总之，一篇好的概要都能体现出简洁性、客观性、完整性和原创性这几大特点。
例1
Design of a Haptic Gas Pedal (气动踏板)for Active Car-Following Support
①The fact that the motor vehicle fatality rate per 100 million vehicle miles has gone down from 5.1 to 1.4 since the 1960s is most certainly the result of improved driver safety regulations,higher driver training standards,better road design,and advancements in car-safety systems. ②From the early seatbelts and anticrash bodles to airbags and side impact protection systems,car manufacturers have come up with a broad range of passive safety improvements that significantly reduce the severity of driver,passenger,and pedestrian or cyclist injury when involved in a traffic accident.
自20世纪60年代以来，每1亿英里的机动车死亡率从5.1下降到1.4，这无疑是由于改进了驾驶员安全法规、更高的驾驶员培训标准、更好的道路设计以及汽车安全系统的进步。从早期的安全带和防车祸罩到安全气囊和侧面撞击保护系统，汽车制造商已经提出了一系列广泛的被动安全改进措施，这些措施大大降低了交通事故中司机、乘客和行人或骑自行车者受伤的严重程度。
③However,with the increased importance of the car as a personal means of transportation,nondriving-related devices,such as car stereos,mobile phones,and,more recently,navigation systems,divert drivers' attention increasingly more away from the primary sources of information necessary for safe operation of the vehicle:the road and other road users. ④With traffic accident statistics attributing driver inattention as one of the major causes of traffic accidents,this increase of in-vehicle devices is worrisome at least-if not dangerous.
然而，随着汽车作为个人交通工具的重要性日益增加，与驾驶无关的设备，如汽车音响、移动电话，以及最近的导航系统，使驾驶员的注意力越来越远离汽车安全运行所必需的主要信息来源: 道路和其他道路使用者。由于交通事故统计数字表明驾驶员注意力不集中是造成交通事故的主要原因之一，车载设备的增加至少令人担忧——如果不是危险的话。
⑤To bridge the gap between the gain in improved passive safety and the increasing development and use of nondriving-related in-vehicle devices,research on car safety systems is directed more towards systems that actively support drivers in their driving task. ⑥Ultimately,active support systems aim to prevent drivers from getting into accidents. ⑦This is a radically different approach compared with that of passive safety systems,which help lessen the impact of driving accidents but do nothing to contribute to preventing drivers from getting into an accident.
为了弥补被动安全性提高与车内非驾驶设备的发展和使用增加之间的空隙，汽车安全系统的研究更多地针对积极支持驾驶员驾驶任务的系统。最终，主动支持系统的目的是防止司机发生交通事故。 与被动安全系统相比，这是一种截然不同的方法，被动安全系统有助于减轻驾驶事故的影响，但对防止驾驶员发生事故毫无帮助。
⑧The goal of this paper is to present the design of an active haptic support systems for car-following. ⑨The intended application range of the proposed system is limited to speeds of approximatey 80 km/h and higher(minimum highway speeds). ⑩The system is intended to provide continuous car-following support within a wide range of car-following situations--not only in critical situations. ⑪The intensity of the support is ,therefore,continuously adapted to the car-following situation.
本文的目的是提出一种主动跟车力觉支持系统的设计方案。拟议系统的预期应用范围限于时速约80公里或更高(最低公路速度)的速度。该系统的目的是在广泛的跟车情况下提供连续的跟车支持——不仅仅是在危急情况下。 因此，支撑的强度不断地适应跟车的情况。
第一段：Motor vehicle death rate is declining year by year.Passive safety improvements played a vital role.
第二段：However, with the car as the main means of transportation, the increase of nondriving-related in-vehicle devices will distract the driver ’s attention and increase the risk of traffic accidents.
第三段：Compared with passive safety systems, active safety systems can prevent drivers from having traffic accidents.while using the in-vehicle devices,it can effectively improve the safety of car-following.
第四段：so we present the active haptic support systems to provide continuous car-following support.