陆旭老师，我有一些做过的assumption题目取非的句子搞不清，你能帮忙看下吗(不说这道题目的解题思路，单纯就是取非问题，特别是双重否定或者从句里面有否定词） 1.No part of a person’s brain that is damaged by a stroke ever recovers.---> some part of a person's brain that is damaged by a stroke ever recovers. 2.Impairment of linguistic capabilities does not occur in people who have not suffered any damage to any language center of the brain.这个句子我不太会取非，正过来说这个句子就是Impairment of linguistic capabilities occurs in people who have suffered any damage to any language center of the brain.那么我取非是Impairment of linguistic capabilities occurs in people who have not suffered any damage to any language center of the brain. 3.If there are language centers on the left side of the brain, any serious stroke affecting that side of the brain damages at least one of them. 取非If there are language centers on the left side of the brain, any serious stroke affecting that side of the brain damages nothing of them. 4.这题出现两个not The collection fee will not significantly affect the purchasing power of most residents, even if their households do not reduce the amount of trash they put out. 我取非直接去前面的not: The collection fee will significantly affect the purchasing power of most residents, even if their households do not reduce the amount of trash they put out. 5.这个也差不多 Not all steel producers were unaffected by country A’s newly imposed tariffs. 我取非All steel producers were unaffected bycountry A’s newly imposed tariffs. 6.There are no plants native to western Africa that, if domesticated, could serve as staple food crops. 这个if domesticated是不是可以不管，直接改成There are some plants native to western Africa that, if domesticated, could serve as staple food crops.

25）有三个stack用来放7个file，7个file中有2个是3m高；有2个是5m高；还有3个是4m高，那么这三个stack中最高的一个stack的最小高度是多少？ 10 题目不太懂 求may老师

求may老师解答

求may老师解答

求may老师

求may老师

老师为什么9k加8可以变成9k加3咧？还有前面（1）那个列出来的式子不是应该3k加1再加1乘以y吗？

老师这道题126除以21是为了干嘛的？拆分最小公倍数嘛？那拆分的形式里面也没有6啊？还有后面的63是哪里来的？是拆分的那个最小公倍数嘛？ 如果在考试中我不能很快速的算出来类似126这样的大数的最小公倍数怎么办？有什么快速算出来的办法吗？谢谢！

求may老师

已知一个五边形有4个角相等，剩余的第5个角比其他4个角小，问这4个角一样的角的度数范围？ 108-135 求may老师解答