According to the passage, in operating airlines it is essential to     .(  )

• A、keep in mind the need. of the executives only
• B、satisfy the need of the low fare passengers at the expense of the executives
• C、try to attract as many passengers as possible by reducing fares
• D、cater to the need of passengers setting at both ends of the jets

A. goal

B. hug

C. entered

D. run

E. promise

F. true

G. proud

H. rest

I. get through

J. encouraging

K. testing

L. preparing

16. Paragraph?17. Paragraph?

18. Paragraph?

19. Paragraph?

20. Paragraph?

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