Hospital statistics regarding people who go to the emergency room after rollerskating accidents indicate the need for more protective equipment. Within this group of people, 75 percent of those who had accidents in streets or parking lots were not wearing any protective clothing (helmets, knee pads, etc.) or any light-reflecting material (clip-on lights, glow-in-the-dark wrist pads, etc.). Clearly, these statistics indicate that by investing in high-quality protective gear and reflective equipment, rollerskaters will greatly reduce their risk of being severely injured in an accident.
The notion that protective gear reduces the injuries suffered in accidents seems at first glance to be an obvious conclusion. After all, it is the intent of these products to either prevent accidents from occuring in the first place or to reduce the injuries suffered by the wearer should an accident occur. 前两句首先肯定了原命题中值得肯定的地方。这是求同存异的表现。注意这里第一句作者同意原命题的同时，在第二句紧接着就给出了展开的证明。而没有光是罗列观点。However, the conclusion that investing in high quality protective gear greatly reduces the risk of being severely injured in an accident may mask other (and potentially more significant) causes of injuries and may inspire people to over invest financially and psychologically in protective gear. 再说原命题是存在逻辑漏洞的，即它因。这里并没有展开论证，因为这是全文的中心句，整个文章都在后面给予论证。同时，最后半句给出了论据中的潜在后果。
First of all, as mentioned in the argument, there are two distinct kinds of gear -- preventative gear (such as light reflecting material) and protective gear (such as helmets). body打头第一段是属于攻击总前提假设的，作者认为这个(即保护性设备和防护性设备的差别)是有必要在讨论一切之前弄清楚的。论证方法为质疑假设，加条件后讨论，提出建议。实际上，这个前提对应的就是开头段的前两句话。深层的含义就是，尽管我在开头对你的某一个部分作了让步似的同意，但是这个同意也是建立在一定的假设基础上的，要是这个假设搞不清楚，哼哼我让不让步还不一定呢!本段就来讨论这个假设基础。Preventative gear is intended to warn others, presumably for the most part motorists, of the presence of the roller skater. It works only if the "other" is a responsible and caring individual who will afford the skater the necessary space and attention. Protective gear is intended to reduce the effect of any accident, whether it is caused by an other, the skater or some force of nature. Protective gear does little, if anything, to prevent accidents but is presumed to reduce the injuries that occur in an accident. 这两句分别从两个方面进行了论述，为本段第一句话的论证进行服务，每一方面的具体方法是先定义，再比较。论证方法为加上不同的条件后进行讨论，比如前一句话假定只有防护性装备会怎样，后一句话假定只有保护性装备会怎么样。The statistics on injuries suffered by skaters would be more interesting if the skaters were grouped into those wearing no gear at all, those wearing protective gear only, those wearing preventative gear only and those wearing both. 这里提出了作者的建议，即如何通过进一步的完善使原命题更加的有力。These statistics could provide skaters with a clearer understanding of which kinds of gear are more beneficial. 如果这个问题(保护防护设备的差别)解决了后面的讨论才能继续。所以说，总的来说这一段是讨论了原文一个核心的前提。