管卫东分析推理(组题)讲义1
分类: Lsat英语
我在逻辑方面的入门书是钱永强老师的那本书,看完了前几部分部分后对分析推理有了一个全面的了解,但对那些有点难度的题目却经常感觉自己缺乏一种洞察力,也就是不知其重点考察哪个条件,矛盾将以何种形式出现在哪里。造成的后果就是作题速度慢, 一开始想多作些题、多总结总结就可以解决这个问题,但作了很多题之后虽有改善却并不显著。
这时我正好得到了一张管卫东老师的讲课录音,花了几十个小时仔细聆听之后,有顿开茅塞之感,接着作了大量练习,终感水平有了质的提高。现我已顺利完成了考试,管老师的一套方法在实践中得到了很好的验证,为使其造福于更多的G友,特将我所做的听课笔记贡献出来。由于录音效果时好时坏,有些地方记录得大概不是很确切,不过总体上应该没什么大问题。
另外要说的就是在管老师的分析方法里,两个根本点是“数目”和“固定”,在对具体题型,分组和排列,的讲解中,也主要是将两个根本点具体化。大家在作题中应仔细体会,最后达到以不变应万变的状态。
最后向管卫东老师致以诚挚的谢意!
一、问题分类与相应的解决方法
组题中的问题大致可分为3类:
1. 问题中有附加条件;
2. 问题中没有附加条件,但有明确的指向。例如某元素不能放在什么位置,某位置不能放何种颜色/形状的元素等。
3. 问题中什么都没给,直接就问下面哪一个是coule be或must be.
第一类问题的解法
先看题干所给的直接条件,再看间接条件,若前两种条件都没有,则要转换对条件的理解方式(角度)。
直接条件:题干中给出的比较明确条件,如:某元素在某些位置,某位置放某些元素,若什么则什么等。
间接限制(条件):
a 数目限制;比如分组时每组的元素数。第一组要放三个元素,现已放两个,那么必须合在一起放的元素就不能放在第一组了。
b 隐式条件,或曰总体条件,它并不特指某个元素,但对全体或多个元素都有约束作用。
转换题目中所给条件的理解方式,例如5个元素排9个位置,现A放1、3,B放5、7,问什 么必然成立?而条件中没有与元素A、B或位置1、3、5、7相关的,似让人感觉无从下手,但我们可以改变条件的理解方式,对上述条件的理解可以改变为9个位置只剩下两个连续的位置(8、9),若题干中有某两个元素应连续出现的条件,则题目就可获得突破。
第二类问题
从下面的例子体会如何通过问题的指向解题。
例一:
A gardener has to plant exactly four varieties of flowers in a flower bed, one variety in each of four rows in an ascending order of height from the first row to the fourth row. The seven varieties available to the gardener are, in ascending order of height, red begonias, pink petunias, orange marigolds, red
geraniums, white snapdragons, yellow zinnias, and pink cosmos. The following restrictions on color arrangements apply:
No two varieties of the same color can be planted.
Orange flowers cannot be planted in a row immediately
adjacent to a row of yellow flowers.
Flowers of which of the following colors CANNOT be planted in the third row? Orange Pink Red White Yellow
例二:
Exactly seven people—Q, R, S, T, X, Y, and Z—serve on an advisory board. Q, R, S, and T have been elected to the board, and X, Y, and Z have been appointed to the board. Three-person or four-person panels are sometimes drawn from the board to study proposals. Each panel must include at least one elected and at least one appointed board member, but no panel can consist of equal numbers of elected and appointed members. Each panel is chaired by a person who is a member of the group of board members (elected or appointed) whose representatives are in the minority on that panel. Any panel must also conFORM to the following conditions:
If Q serves on a panel, T cannot serve on that panel.
If R serves on a panel, X cannot serve on that panel.
T and Y cannot serve on a panel unless they serve together.
If Z serves on a panel, X must also serve on that panel.
Each of the following could chair a panel EXCEPT
S
T
X
Y
Z
第三类问题:
解第3类问题的步骤:(问题中什么都没给,直接就问下面哪一个是coule be,can not be或must be)
1. 迅速看一眼选项,知道选项针对的是什么性质;
2. 看涉及此种性质的条件。问题若是coule be,则找最不固定化的元素;若是can not be或must be,则找最固定化的元素。固定化条件
优先看;
3. 找涉及此元素的选项;
4. 对选项加以验证。(若时间紧,也可以不验证)
若选项未提供有用信息,则立刻从数目和隐式条件着手。
例:
Six musicians—Ann, Betsy, Gordon, Juan, Marian, and Ted—are planning to perFORM a program consisting entirely of three quartets. Each quartet requires two violins, one cello, and a piano. Each person must play in at least one quartet, and each person can play, at most, one instrument in a quartet. No person can play the same type of instrument (violin, cello, or piano) in two successive quartets.
这时我正好得到了一张管卫东老师的讲课录音,花了几十个小时仔细聆听之后,有顿开茅塞之感,接着作了大量练习,终感水平有了质的提高。现我已顺利完成了考试,管老师的一套方法在实践中得到了很好的验证,为使其造福于更多的G友,特将我所做的听课笔记贡献出来。由于录音效果时好时坏,有些地方记录得大概不是很确切,不过总体上应该没什么大问题。
另外要说的就是在管老师的分析方法里,两个根本点是“数目”和“固定”,在对具体题型,分组和排列,的讲解中,也主要是将两个根本点具体化。大家在作题中应仔细体会,最后达到以不变应万变的状态。
最后向管卫东老师致以诚挚的谢意!
一、问题分类与相应的解决方法
组题中的问题大致可分为3类:
1. 问题中有附加条件;
2. 问题中没有附加条件,但有明确的指向。例如某元素不能放在什么位置,某位置不能放何种颜色/形状的元素等。
3. 问题中什么都没给,直接就问下面哪一个是coule be或must be.
第一类问题的解法
先看题干所给的直接条件,再看间接条件,若前两种条件都没有,则要转换对条件的理解方式(角度)。
直接条件:题干中给出的比较明确条件,如:某元素在某些位置,某位置放某些元素,若什么则什么等。
间接限制(条件):
a 数目限制;比如分组时每组的元素数。第一组要放三个元素,现已放两个,那么必须合在一起放的元素就不能放在第一组了。
b 隐式条件,或曰总体条件,它并不特指某个元素,但对全体或多个元素都有约束作用。
转换题目中所给条件的理解方式,例如5个元素排9个位置,现A放1、3,B放5、7,问什 么必然成立?而条件中没有与元素A、B或位置1、3、5、7相关的,似让人感觉无从下手,但我们可以改变条件的理解方式,对上述条件的理解可以改变为9个位置只剩下两个连续的位置(8、9),若题干中有某两个元素应连续出现的条件,则题目就可获得突破。
第二类问题
从下面的例子体会如何通过问题的指向解题。
例一:
A gardener has to plant exactly four varieties of flowers in a flower bed, one variety in each of four rows in an ascending order of height from the first row to the fourth row. The seven varieties available to the gardener are, in ascending order of height, red begonias, pink petunias, orange marigolds, red
geraniums, white snapdragons, yellow zinnias, and pink cosmos. The following restrictions on color arrangements apply:
No two varieties of the same color can be planted.
Orange flowers cannot be planted in a row immediately
adjacent to a row of yellow flowers.
Flowers of which of the following colors CANNOT be planted in the third row? Orange Pink Red White Yellow
例二:
Exactly seven people—Q, R, S, T, X, Y, and Z—serve on an advisory board. Q, R, S, and T have been elected to the board, and X, Y, and Z have been appointed to the board. Three-person or four-person panels are sometimes drawn from the board to study proposals. Each panel must include at least one elected and at least one appointed board member, but no panel can consist of equal numbers of elected and appointed members. Each panel is chaired by a person who is a member of the group of board members (elected or appointed) whose representatives are in the minority on that panel. Any panel must also conFORM to the following conditions:
If Q serves on a panel, T cannot serve on that panel.
If R serves on a panel, X cannot serve on that panel.
T and Y cannot serve on a panel unless they serve together.
If Z serves on a panel, X must also serve on that panel.
Each of the following could chair a panel EXCEPT
S
T
X
Y
Z
第三类问题:
解第3类问题的步骤:(问题中什么都没给,直接就问下面哪一个是coule be,can not be或must be)
1. 迅速看一眼选项,知道选项针对的是什么性质;
2. 看涉及此种性质的条件。问题若是coule be,则找最不固定化的元素;若是can not be或must be,则找最固定化的元素。固定化条件
优先看;
3. 找涉及此元素的选项;
4. 对选项加以验证。(若时间紧,也可以不验证)
若选项未提供有用信息,则立刻从数目和隐式条件着手。
例:
Six musicians—Ann, Betsy, Gordon, Juan, Marian, and Ted—are planning to perFORM a program consisting entirely of three quartets. Each quartet requires two violins, one cello, and a piano. Each person must play in at least one quartet, and each person can play, at most, one instrument in a quartet. No person can play the same type of instrument (violin, cello, or piano) in two successive quartets.