例二：

　　Accustomed though we are to speaking of the films made before 1927 as “silent”, the film has never been, in the full sense of the word, silent. From the very beginning, music was regarded as an indispensable accompaniment; when the Lumiere films were shown at the first public film exhibition in the United States in February 1896, they were accompanied by piano improvisations on popular tunes. At first, the music played bore no special relationship to the films; an accompaniment of any kind was sufficient. Within a very short time, however, the incongruity of playing lively music to a solemn film became apparent, and film pianists began to take some care in matching their pieces to the mood of the film.

　　What can be inferred from the passage about the majority of films made after 1927?

　　(A) They were truly “silent.”

　　(B) They were accompanied by symphonic orchestras.

　　(C) They incorporated the sound of the actors’ voices.

　　(D) They corresponded to specific musical compositions.

　　1927年前后形成对比。既然1927年以前的电影只有音乐而没有配音，那么1927年之后的电影一定有。所以(C)为正确答案。

　　例三：

　　“…The nineteenth century brought with it a burst of new discoveries and inventions that revolutionized the candle industry and made lighting available to all. In the early-to-mid-nineteenth century, a process was developed to refine tallow (fat from animals )with alkali and sulfuric acid. The result was a product called stearin. Stearin is harder and burns longer than unrefined tallow. This breakthrough meant that it was possible to make tallow candles that would not produce the usual smoke and rancid odor. Stearins were also derived from palm oils, so vegetable waxes as well as animal fats could be used to make candles …”

　　Which of the following can be inferred from paragraph 1 about candles before the nineteenth century?

　　¡They did not smoke when they were burned.

　　¡They produced a pleasant odor as they burned.

　　¡They were not available to all.

　　¡They contained sulfuric acid.

　　问题：关于19世纪以前的蜡烛，从第一段可以推出下列哪一点？

　　这道题的题干中有“19世纪以前”这一时间，由此可见它属于“时间对比推理”思路。原文首句指出：“…19世纪带来了大量新发现和发明，使蜡烛业发生了革命性的变化，所有人都能用蜡烛照明。” 根据“时间对比推理”思路，由于19世纪以前的情况与19世纪形成对比，而19世纪所有人能用蜡烛照明，那么在19世纪之前，并非所有人都能用上蜡烛。第三个选项 “They were not available to all”表达了这一意思，为正确答案。

　　2.集合概念推理

　　集合概念推理也可以称之为百分比推断，它指的是在一个集合中，包含两个相对的方面，共同构成一个大的集合。一方所占的比例减少意味着另一方所占比例的增加；反之，一方所占的比例增加意味着另一方所占比例的减少。根据这一思路，可以由集合中一方的数量变化推断另一方的消减。

　　例一：

　　A folk culture is small, isolated, cohesive, conservative, nearly self-sufficient group that is homogeneous in custom and race, with a strong family or clan structure and highly developed rituals. …Unaltered folk cultures no longer exist in industrialized countries such as the United States and Canada….