GRE网络课堂学习笔记-逻辑[10]

4. Questions 13-18

In a game, "words" (real or nonsensical) consist of any combination of at least four letters of the English alphabet. Any "sentence" consists of exactly five words and satisfies the following conditions:
The five words are written from left to right on a single line in alphabetical order.
The sentence is started by any word, and each successive word is formed by applying exactly one of three operations to the word immediately to its left: delete one letter; add one letter; replace one letter with another letter.

At most three of the five words begin with the same letter as one another.
Except for the leftmost word, each word is formed by a different operation from that which formed the word immediately to its left.

(13). Which one of the following could be a sentence in the word game?
(A) bzeak bleak leak peak pea
(B) crbek creek reek seek sxeek
(C) dream gleam glean lean mean
(D) feed freed reed seed seeg
(E) food fool fools fopls opls

(14). The last letter of the alphabet that the first word of a sentence in the word game can begin with is:
(A) t
(B) w
(C) x
(D) y
(E) z

(15). If the first word in a sentence is "blender" and the third word is "slender" then the second word can be:
(A) bender
(B) gender
(C) lender
(D) sender
(E) tender

(16). If the first word in a sentence consists of nine letters, then the minimum number of letters that the fourth word can contain is
(A) four
(B) five
(C) six
(D) seven
(E) eight

(17). If "clean" is the first word in a sentence and "learn" is another word in the sentence, then which one of the following is a complete and accurate list of the positions each of which could be the position in which "learn" occurs in the sentence?
(A) second
(B) third
(C) fourth, fifth
(D) second, third, fourth
(E) third, fourth, fifth

(18). If the first word in a sentence consists of four letters then the maximum number of letters that the fifth word in this sentence could contain is :
(A) four
(B) five
(C) six
(D) seven
(E) eight

KEYS: BDCDEC