熱血背包客莊 ㄟ

GRE - T-25

命題表
P  （前提）	Q （結論）	P →Q （命題）	老師出題/ 學生答案
T	T	T	有拿分
T	F	F	你打錯不給分
F	T	T	題目出錯送分
F	F	T	題目出錯送分

 

其實定理源自於中國古老戰國時期的百家爭鳴年代

名家公孫龍說到『白馬非馬』

惠施有天跟莊子莊子曰：「鯈魚出游從容，是魚之樂也。」

惠子曰︰「子非魚，安知魚之樂？」

惠施說到，你不是魚你怎麼知道魚快不快樂。

不過後來任賢齊證實了『魚好像不快樂』。

我引用李祥老師的說法，把Ｐ當作是老師出題，然後學生作答當作Ｑ，接著有四種情形，老師如果出提示出隊的情況下，就跟我們考試一樣，答對給分，答錯就是錯，看是倒扣或是不扣分。接著一定會碰到那種老師題目出錯，然後學生還是作答的情況下，這樣學校就會公告說某某科第幾題，送分！！！以前聽到都會爽歪歪，因為不管有沒有答對，都算分，算你答對了，所以回看這張表假設P →Q當作是有沒有拿分，拿到給Ｔ沒拿到給Ｆ，這樣就好記多了。

 

如果你把它拿來對照GRE critical thinking的考題的話，你會發現P →Q （命題）就是argument，P  就是前提，Ｑ就是結論。這樣假設題目問你weaken的時候，你看到第二行，嘿嘿，將選項帶入找到一個可以讓Ｑ是錯的，這樣就好找了，一樣道理support或是strengthen就是找第一行就好，那如果是evaluation 題型就是找到一個選項使得選項如果取肯定含義Ｑ會是Ｔ，取負面含義，Ｑ會變Ｆ。最後如果是assumption這個就是找一個Ｐ的意思，所以找選項的一個可以變成Ｔ的Ｐ，最後P →Q （命題）也是Ｔ即可。

 

買數學送英文，再送國文，耶！！！

 

狄摩根定律，一切都變了！！

～(Ｐ＾Ｑ) = ~ P  V ~ Q

~ ( P V Q ) = ~ P ^ ~ Q

例如：高且帥，所以轉換後等價『不高或不帥』

(X-1) (Y-2) = 0, X=1 V Y=2

否定 ：(X-1) (Y-2) =/= 0 (不等於), X=/= 1 ^ Y=/= 2

 

例題1：

若 3x +2y = 16, 則 2x-y =/= -1 是假的

所以老師出對題，學生答錯了，為了使得命題正確，所以自動改成

2x-y = -1，之後就是聯立方程式了

答：X=2 ^ Y=5 

例題2：

有哥→沒弟

沒哥→有妹

沒姐→有弟Ｖ有妹 （後方用迪摩根）

所以利用逆否命題可得等價

有弟→沒哥

沒妹→有哥

沒弟＾沒妹→ 有姐

是問如果沒有妹妹，會怎樣，答案是有姐

Ans: 因為沒有妹妹，會得到 『有哥』

        然後有哥，又會變成『沒弟』，

        此時湊齊『沒弟＾沒妹』，所以最後變成『有姐』。

 

 

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Verbal:

Article one : (From GRE offical guide )

The passage suggests that population fluctuations in many other animal species differ from those of the snowshoe hare in that population fluctuations in other species

(A) are less regular due to more erratic changes in predator levels

(B) typically occur over a longer time period

(C) are synchronized over larger areas

(D) are less dependent on food availability

(E) are typically less predictable

 

Ans: (E)

Key) "differ from" is the key，and then we are requested to find the other species's difference. So, we have to find the hare characteristic and then its opposite site is the answer. Located the sentecne: 

The cycle of fluctuation in snowshoe hare populations is unusual among animal species in that it is remarkably regular-peaking every eight to eleven years-and broadly synchronized over a vast area

so the other species is irregular and no synchronized, So seaily to konw the answer is (E)

 

According to the passage, biologists have suggested which of the following about snowshoe hare population fluctuations?

(A) Their regularity is due to the persistent threat of malnourishment that young hares face.

(B) They are similar in length to those of other species of hare.

(C) Their synchrony can be partly explained by the ability of predators to change the areas in which they hunt.

(D) Their variation from region to region is partly due to regional differences in the availability of alternate prey for predators.

(E) Their regularity is due to the constant availability of the food sources hares rely on.

 

Ans: (C)

Key) "suggested" means when we find the answer, we need to look for the related information among all materials about snowshoe hare population fluctuations

So, the target is here, 

Some biologists hypothesize that the cycle begins when peak snowshoe hare populations exceed their winter food supply; resulting malnutrition triggers a population decline.

The fluctuations are related to food. but actually take the sentence seriously, cuz it says about the detail of decline and peak of the flucturations.

As hare numbers fall, the ratio of predators to hares increases, as does the impact of predation on the hare population. This extends the decline beyond the period of winter food shortage. Hare scarcity then causes predator population declines, and with fewer predators and more abundant winter food, the hare population begins another cyclic increase.

These sentences can be ignore, because our main goal is the fluctuations, not the detail of fluctuations. When the article talks about the number fall or decline or increase, they are all the phenomena in the fluctuations. 

The high mobility of predators responding to local differences in hare abundance contributes to interregional synchrony.

Mobility of predators is eaqual to flucturations, and this cause interregional synchrony. Then we combine all of them; the first sentence and the last one. we have got food supply up and down, and then we have got predators cause interregional synchrony. (C)

 

The passage suggests that which of the following is true of fluctuations in snowshoe hare populations?

(A) Changes in hare population levels are not highly correlated with changes in predator population levels.

(B) Hare populations in one region are unlikely to peak at the same time that populations in nearby regions are at the lowest point of the cycle.

(C) The regularity of hare population fluctuations is greater in regions where populations peak every eight years than in regions where they peak every eleven years.

(D) In areas where hare population cycles are greater than eleven years, predator mobility is unusually high.

(E) Fluctuations in hare populations vary greatly from region to region, depending on available winter food supply.

 

Ans: (B)

Key) the target is the same to the question2, and it is all about synchrony

(B) talks that the time of peak unlikely happened at the time of nadir nearby regions. They artually synchronzie. One place's hare population goes up, and the place proximity to it goes up too, vice versa. 

 

Article two : (From GRE offical guide )

 

Ans: (E)

Key) when we see suggestion, we need to read more than target sentence. Its upper or lower sentence are also involved to construct a conclusion which sastify the question. In this one, readers of the earliest books printed in Europe is the target. But normally we will not find "earliest" in the argument, judging from my chronologically personal experences. From the information, we should assume or expect that the article would mentioned early-related words or anti-early words which faciliate to comparison. So, let's go. By looking at the first sentence, we already find the key word

The first printers in Europe modeled their books very closely on handwritten manuscripts, leading to an easy acceptance of print among readers but to significant missteps in trying to apply technology.

Then we check out if there are the same meaning of "leading to an easy acceptance of print among readers" in the choices. "The easy" matches  the familar of (E)

 

 

Text 1: (From GRE offical guide )

Blank(i)	Blank(ii)	Blank(iii)
(A) apathy underlying	(D) impervious	(G) humility
(B) candor in	(E) accustomed	(H) obfuscation
(C) optimism resulting from	(F) antagonistic	(I) railery

Ans: (B), (E), (H)

Key) the key is "departure" and , meaning that government is corrupt. So we need a opposite meaning of departure to fill up the blank(i), and then (B) candor is the answer. It says that it is surprised that government are doing something with candor, which make people feel a stound.

Second key is blandness which means boringness, and then we can see a adjective clause to supportively describe blandness and blank(iii). Since the adjective clause says the characteristic is typical, we can be sure that Blank(ii) is (E) accoustomed. And for usual VS. occasional, they are opposite, so chose a work which is contrary to blandness. So (H) is.  

 

 

 

 

 

 

以上筆記彙整，再請多指教