《2024年绿色通道45分钟课时作业与单元测评英语选择性必修第三册》

I.阅读理解
　　The number of birds in North America has declined by almost 3 billion since 1970, according to a study published in Science. The researchers estimated changes in the populations of 529 species using long−term bird−monitoring databases. Those data showed that the number of individual birds across all of those species had decreased by 29 percent, from around 10 billion in 1970 to just over 7 billion in 2017.
　　“The data they used provide probably the best long−term, large information on species abundances for any group of animals or plants anywhere in the world,” Natalie Wright, a bird biologist tells The Atlantic. “There's always uncertainty, but if they are wrong, they are likely underestimating the size of population declines."
　　The team also examined 10 years’ worth of data from a network of 143 weather radars, which picked up bird migrations, and found a reduction in migratory biomass of about 14 percent since 2007. “Two completely different and independent monitoring techniques thus signal major population loss across the continent," the authors wrote in their paper.
　　The results are particularly concerning because many of the species showing declines are not considered rare or in danger, but are almost everywhere and potentially act as important contributors to food webs and ecosystem function. More than 90 percent of the loss in abundance in the survey data was due to declines in 12 families, including sparrows and blackbirds. Some other species, including many ducks, instead showed increases in abundance−possibly as a result of focused conservation efforts in recent years.
　　The findings should be a wake−up call. Many of the birds studied spend time in multiple countries within and beyond North America. What our birds need now is a historic, global effort that unites people and organisations with one common goal: bringing our birds back.

1. How does the first paragraph show the bird reduction?
A. By comparing figures.
B. By listing some examples.
C. By using experts' words.
D. By doing experiments.
2. What can we infer about the function of the data according to Natalie Wright?
A. It's wrong.
B. It's formal.
C. It's helpful.
D. It's useless.
3. Which of the following is particularly worrying?
A. The focus of conservation efforts has turned out wrong.
B. Some ducks are likely to lose their ecosystem function.
C. Few species across the continent show the increase.
D. The population of widespread species is declining.
4. What is the author's purpose in writing the text?
A. To point out the importance of raising birds.
B. To call on people to work together to bring birds back.
C. To analyse the concerning results of long−term research.
D. To inform people of the dangers many species are facing.

答案： 1.A 细节理解题。根据第一段最后一句可知，第一段是通过对比1970年和2017年鸟类个体的数量来表明鸟类的减少的。故选A。
2.C 推理判断题。根据第二段第一句可推断，这些数据对于人类了解物种的丰富程度有很大的帮助。故选C。
3.D 细节理解题。根据第四段第一句可知，一些作用重要且广泛分布的物种的数量也在减少，这是最令人担忧的。故选D。
4.B 写作意图题。根据最后一段第一句“The findings should be a wake-up call.”和最后一句可推知，作者在文章中指出鸟类物种数量减少的现象是为了号召人们一起合作，从而挽回鸟类数量逐渐减少的局面。故选B。