21. It was once believed       ,and thus we can tell how successful he/ she will be in the future according to his/her intelligence.

22. More recent researches has shown that intelligence is only partly inherited      .

23. We. can observe and measure observed intelligence, but genetic intelligence      .

24. It can be inferred from the passage that a child will      if he has more opportunities to communicate with others by means of language.

25. Children were not just      ,but they can be taught to be more intelligent at school.

A. born to be more intelligent or less intelligent

B. have 8 better chance to develop, his intelligence

C. can't be observed and measured

D. that intelligence was something a baby was born with

E. and because of the lack of communication with his classmates

F. and partly has to do with a child's living environment

16. Paragraph➊17. Paragraph❷

18. Paragraph❸

19. Paragraph❹

20. Paragraph❺

A. Main Results of Recent Researches

B. Difference between Genetic and Observed Intelligence

C. Effect of Environment on Intelligence

D. Intelligence and Achievement

E. Impact on School Education

F. A Changed View of Intelligence

The following are all mentioned as reasons why the airlines are having a hard time EXCEPT that     .(  )

• A、the tourist industry is experiencing an all-time low
• B、there is no increase in the number of passengers
• C、there are more seats on the planes than needed
• D、the competition between airlines is strong