There is no doubt that adults, and even highly educated adults, vary greatly in the speed and efficiency of their reading. Some proceed very lowly throughout; others dash along too quickly and then have to regress. Poor readers in particular may lack the ability to vary their manner of reading according to the type of reading matter and to their intentions in reading it. A good reader can move at great speed through the text of a novel or similar light reading matter. He may be able to skim a page, picking up a word or two here and there, and gain a general idea of what the text is about without really reading it. In reading more difficult material, with the intention of taking in the whole of it, he will proceed more slowly, but even then he will vary his pace, concentrating on the key words and passages, perhaps re-reading them several times and pass more quickly over the remainder. A less efficient reader tends to maintain the same speed whatever the material he reads. Consequently, even light reading matter gives him little pleasure because he reads so slowly. But this pace may be too fast for really difficult material which requires special concentration at difficult points.
A type of reading which necessitates(需要) careful attention to detail is proofreading, in which the reader, in order to detect misprints in a sample print, has to notice not so much the meaning of what he reads as the exact shape and order of letters and words in the text. This is extremely difficult for most people, since they are accustomed to overlooking such details. In fact, considerable practice is required to practise this task efficiently and it can be done only by reading very slowly, and by paying comparatively little attention to the general meaning of the text.
68．This article is mainly concerned with ________.
A．the ability to read fast      
B．difference in the speed and efficiency of reading
C．different reading skills      
D．the reading speed of highly educated adults
69．According to the article, there is a difference in reading speed ________.
A．among adult readers
B．among young educated people
C．among readers who have different experiences
D．between the poorly educated and the highly educated
70．The underlined word "regress" can be best replaced by "________".
A．regret         B．stop   C．move slowly       D．go back
71．The author believes a good reader should ________.
A．always read at great speed      
B．read carefully and catch every detail
C．always review the text he has read 
D．change his speed according to the type of text