【昨日回顾】In general，the tests work most effectively when the qualities to be measured can be most precisely defined and least effectively when what is to be measured or predicted can not be well defined.一般来说，当所要测定的特征能很精确界定时，测试最为有效;而当所要测定或预测的东西不能明确地界定时，测试的效果则最差。【今日长难句】Properly used，these tests provide a rapid means of getting comparable information about many people. Sometimes these tests identify students whose high potential has not been previously recognized，but there are many things they do not do.
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【基础必备词】properly adv. 适当地；正确地；恰当地comparable adj. 可比较的；比得上的、identify vt. 确定；鉴定；识别，辨认出potential n. 潜能；可能性；previously adv. 以前；预先；recognize vt. 认出，识别；承认【句子分析】1. 首句主干为主谓宾= they + provide +a rapid means of getting comparable information about many people. 修饰成分：properly used 为非谓语动词（V-ed形式）作状语，properly used = if/when they are properly used2. 二句主干为but连接的并列句：they identify students, but there are many things. 修饰成分：sometimes 为时间状语；whose high potential has not been previously recognized 为定语从句，修饰students。3. they do not do 为省略关系词的定语从句，修饰many things。but there are many things they do not do 是翻译的难点所在。they 指代 these tests, do替代上文中出现过的identify.【参考译文】Properly used，these tests provide a rapid means of getting comparable information about many people. Sometimes these tests identify students whose high potential has not been previously recognized，but there are many things they do not do.这些测试如能恰当使用，就能提供一种快速的方法来获得有关许多人的可比性信息。有时这些测试能鉴别出一些学生，其较高的潜能过去一直没有被认可。但是也有很多东西是这些测试无法鉴别的。【明日预告】For example，these tests do not compensate for gross social inequality，and thus do not tell how able an underprivileged youngster might have been had he grown up under more favorable circumstances.
