In the country of Veltria, the past two years' broad economic recession has included a business downturn in the clothing trade, where sales are down by about 7 percent as compared to two years ago. Clothing wholesalers have found, however, that the proportion of credit extended to retailers that was paid off on time fell sharply in the first year of the recession but returned to its prerecession level in the second year. Which of the following, if true, most helps to explain the change between the first and the second year of the recession in the proportion of credit not paid off on time? (A) The total amount of credit extended to retailers by clothing wholesalers increased between the first year of the recession and the second year. (B) Between the first and second years of the recession, clothing retailers in Veltria saw many of their costs, rent and utilities in particular, increase. (C) Of the considerable number of clothing retailers in Veltria who were having financial difficulties before the start of the recession, virtually all were forced to go out of business during its first year. (D) Clothing retailers in Veltria attempted to stimulate sales in the second year of the recession by discounting merchandise. (E) Relatively recession-proof segments of the clothing trade, such as work clothes, did not suffer any decrease in sales during the first year of the recession. 这道题错选了A。 思路如下： 题目问的是为什么在经济不好，衣服卖不动的情况下，第一年零售商还不上钱第二年就能还上了。讲的是零售商还钱的问题。 当时留下的是A,C,D 排除D是因为觉得，即使刺激销售量衣服打折也不能说明能还上钱。可能打折卖1块，纵使家当全卖了也不够。 排除C是因为觉得， 那些本身经济状况就很差的在第一年被淘汰掉以后，剩下的那些没说经济状况如何啊，如果也不咋地，第二年还是得淘汰啊。 A选项当时觉得，即使credit extended，对pay off on time也无太大用处，但最起码跟原文意思接近。所以选了A。

为什么critique和envisioning不算并列？划线部分做同位语作用，为何不能用起伴随作用的DE？as well as是否既可以用在两者比较又可以用在三者？

请数学老师解答

请问数学老师 条件中 each more than 3 feet from the nearest wall 这个条件有什么用？再说下思路 谢谢老师

请问数学老师 条件2怎么可以快速推算结果

老师 我不太懂什么k一定是4的倍数呢？

ken老师这道题目答案对吗？为什么说两个条件中的方程是同一个方程啊，我算出来不一样，当条件1&2同时存在时，两个方程是有两个交点，应该就是可以判断出（a,b)的值吧？

请问数学老师 这个题如何在短时间内快速得出答案

ken老师 这道题目黄色部分我不太明白，An和n各自代表什么意思？我以为An代表的整数列所有数的合，那n不可能小于100呀，好奇怪

麻烦金老师回答，主要的困惑在于AB两个选项。一个that位置的不同，和will 和 would 的不同。刚开始我的思路是旅客会更多的使用旅行机构这件事是一个预测，没发生的，虚拟语气所以就错选了B.will 和would 的区别是 will 表达的感觉更确定一点吗？

麻烦金老师回答，这题看到DIGGING 这个动作是人发出的 不可能是化石发出的，排除AB ，C 里面的it 指代不是很清楚。对比DE， 这个化石来自那里这个部分的内容比较长所以D 选项是用了一个从句来说明的意思吗？就是关于DE选项的appears 和 APPEAR 这个差一点我不是很清晰，还是说D这个答案的what 这个选项引导的从句直接修饰到bones上，所以胜出？