A．It can be seen even in dark areas.

B．It represents danger in many cultures.

C．It has the longest wavelength.

D. People prefer red to other colors.

27．Which of the following may the author agree with?

A．The meaning of red is culture­specific.

B．Yellow functioned as stop signs in the 1900s.

C．Green's wavelength is just second to that of red.

D．Green's role in lights has changed over time.

28．What does the passage mainly talk about?

A．The significance of road traffic signs.

B．The history of railroad transportation.

C．The symbolic meaning of different colors.

D．The origin and development of traffic lights.

25-28.ACDD

完形填空

阅读下面的短文，掌握其大意，从各题所给的四个选项中选出最佳选项。

Ten-year -old Riley Christensen and her mother，Lynn，sat in front of the family computer，checking out models and prices of bikes. "Let's 41 one out for Dad's birthday present，"Lynn suggested to her daughter.

As Riley surfed the home page of the Bike Rack，a 42 in their town caught her eye. She clicked it out of curiosity. The 43 told how Bike Rack owner Hal Honeyman had created an organization to 44 specially engineered bicycles for people with disabilities. It also showed the 45 faces of those who were riding them， 46 Hal's own son，who had been born with cerebral palsy (脑瘫)．

"I'm going to 47 a bike for one of those kids，"Riley told her mother. Two days later，she showed her mother a 48 she had written asking for donations. Lynn was encouraged by her daughter's effort， 49 doubts quickly came. The 50 of just one of those special bikes could be as much as $ 4,000.Riley could never raise the money. However，her letter went out to 75 relatives and friends. Within 3 days，checks and cash began 51 .Then word 52 about Riley's 53 ，and as Christmas drew near，more and more donations rolled in. The teen 54 raised more than $ 12,000，enough to pay for three bikes.

Last Christmas Eve，Riley delivered the bicycles to three of the 55 disabled kids: Ava，Jenny and Rose. "This is the 56 Christmas I have ever had，"said Ava. Since then，Ava and Jenny have 57 together. "When I ride，I like to go fast，get sweaty，and feel the 58 ，"Jenny says. "So does Ava. She rides the bike with her arms，not her feet，but she really feels she is 59 ."

Riley is 60 to keep her campaign going every holiday season. "I want kids to feel the wind in their faces，"she says.

41．A. pick　　　　　 B．give

C．sell D．send