扩大范围，条件是 in its class，结论是当今最安全的车之一。削弱：那个类型的车就是爱出事故，你是那个类型最安全的也不顶用。
pronounced：noticeable 明显的

B:provided there are two types of switches--- mechanical & electronic.The former are more invulnerable B create a new chip made of 12,000 electronic SWITCHES,attempting to mislead us that such chip is made of 12,000 invulnerable mechanical switches.But the key is that however many electronic switches a chip consist of， electronic switches are more vulnerable than mechanic ones .

C除了they them指代的executives是放在所有格中出现的，不太好
还有一个重要的点‘’is heavily committed‘’这个重要信息被放进essential modifier中成了次要信息

全划线的句子除了注意句子结构之外也要注意一些句子中的小点（往往是平行之类的很简单的点），其实有时候过于注重大结构和intended meaning 也会导致漏看一些很明显的错误点

注意 being通常做主语 表示某一种状态（noun）的时候往往不是多余的

①remember this as an idiomatic usage of the construction \"known to\". if the action is in the present, then you use \"known to VERB\"; if the action is in the past, then you use \"known to have VERBed\". as far as i know, these are the only two possible forms.
②date to/at区分
1) date….to 可追溯sth到...几年，强调发生的时间点，后面是ago
2) date….at 年代判定、鉴别/年份有….年之久，强调发生到现在经过的时间有多长，后面是old

注意体会AB的intended meaning不一样了
pushing back by more than 150,000 years the earliest date /when it is known that humans made stone tools./
将/知道了人们制作石头工具的的日期/推迟 注意体会这个it is known that...

The persistent efforts of African American unionists eventually paid off: many became highly effective organizers, gaining the respect of even racist White unionists by winning victories for White as well as African American workers.

the product of all the different positive prime factors of n is less than the square root of n.
用枚举法解决的，不知道还有没有更简便省时的方法？

gp: conclude to sb's satisfaction

这道题Helr给出的情景翻译少翻了一句话： to all employees

好像去北京见HELR，可是我在福州。

p^2)*q=multiple of 5
∴q=5z（z is integer）
∴q^2 =25K
∴B???????????????

关键要读懂第二段的首句 以及理清关系
前两个人不好 有一个trend那就是学者们都反对那两人
第二段开头就说 同时这个反对的trend也存在于TK的研究当中 人们也反对tk的研究 tk虽然有所建树 但还是狭隘了
我愣是看不出来 tk的观点哪里反对 前两人的观点了 明明tk自己也是被反对的一方

错误选项a，错误原因，最后一段提出了前面两段没出现过的 modern educator，modern social worker，所以不是summarize，而是提出新的evidence去support，Nightingale's brilliance and creativity.

作者态度很鲜明，不是客观的去reconcile两个观点的。

这么看来气温好像和飞行能力正比

C说明预测总是正确的

没有痕迹只能说明人们带走啦

wean 不知道是断奶的意思··· 就选了D，以为年龄和断奶有关系···