Although spinach is rich in calcium, it also contains large amounts of oxalic acid, a substance that greatly impedes calcium absorption by the body. Therefore, other calcium-containing foods must be eaten either instead of or in addition to spinach if a person is to be sure of getting enough calcium.
Which of the following, if true, most seriously weakens the argument above?
(A) Rice, which does not contain calcium, counteracts the effects of oxalic acid on calcium absorption.
(B) Dairy products, which contain even more calcium than spinach does, are often eaten by people who eat spinach on a regular basis.
(C) Neither the calcium nor the oxalic acid in spinach is destroyed when spinach is cooked.
(D) Many leafy green vegetables other than spinach that are rich in calcium also contain high concentrations of oxalic acid.
(E) Oxalic acid has little effect on the body's ability to absorb nutrients other than calcium.
直接從Argument定義著手，如果想知道更詳細的內容，出門左轉往前幾篇參考，這裡就不多贅述了，首先把它變成一個在批判性思維當中的一個術語就是（logic book style）就是把每一句話所扮演的角色給標定清楚
premise1: Although spinach is rich in calcium, it also contains large amounts of oxalic acid
premise2: oxalic acid is a substance that greatly impedes calcium absorption by the body
conclusion: Therefore, other calcium-containing foods must be eaten either instead of or in addition to spinach if a person is to be sure of getting enough calcium.
這裡為了更為詳細才細分前提，以同位語當分界，但是考試因為時間限制盡量以單句為一個組別
前提一：S= Ca+OA
前提二：OA 反 Ca
結論：要Ca就要吃別的Ca物
然後針對題目問到的weakens the argument 做分析，waeken這個弱化，就是使得argument變成一個爛argument，(valid→ invalid arguments)，而剛剛提到一個論辯就是數個前提加上一個結論，假設這當中前提可以被質疑，（Is the premiese ture? 這個問題一定要考試時不斷的問自己），使得結論具有極大不確定性，這就是弱化整個論辯，或是另一個呈現方式：當我的論辯當中結論的部分是可以找到一個反例，那我就達成弱化的目的了，因此用這兩個方法去找答案，這裡補充說明定義說明
validity---
If and only if …
There is no possible situation in which..
All premises are true…
And its conclusion is false.
所以只要在前提是『真』的情形下，而結論卻是『錯』的，那這組論辯會馬上由valid變成in-valid，而這個過程就是weaken
做題：
所以我要找到一個對結論的反例也就是『要Ca，就要吃別的Ca物』這件事是錯的，更白話一點就是，吃沒有Ca的食物也可以有鈣質。所以原文的結論會在主要句子當中加個『not』
Therefore, other not calcium-containing foods must be eaten either instead of or in addition to spinach if a person is to be sure of getting enough calcium. 選項當中能夠使這句更改後的結論成立，那就達成weaken的作用了
(A) Rice, which does not contain calcium, counteracts the effects of oxalic acid on calcium absorption. rice= other food without calcium, counteract oxalic acid= absorb enough Ca.
其他選項補充：
(B) Dairy products, which contain even more calcium than spinach does, are often eaten by people who eat spinach on a regular basis. 多吃鈣，頭好壯壯，這沒有削弱反而加強，而且他有跟整個論辯主角連貫
(C) Neither the calcium nor the oxalic acid in spinach is destroyed when spinach is cooked. 單就毀滅跟川燙是不可以和結論有任何連貫性的
(D) Many leafy green vegetables other than spinach that are rich in calcium also contain high concentrations of oxalic acid. 討論其他蔬菜的組成物，雖然是不可以推出要多吃其他含鈣食物才不會缺鈣，但是它離題了，並沒有連貫性，我們的連貫性都在討論『鈣質的吸收』
(E) Oxalic acid has little effect on the body's ability to absorb nutrients other than calcium. ＯＡ不影響其他養分吸收，這個也跑題了，主角是鈣質可否吸收
在連貫性跟argument的定義下作題，就不易陷入翻譯找答案的陷阱中了。以上個人筆記希望有幫助到大家，有誤再請指教!!
托福TOEFL ibt (4)