loadingtheir own.
In both cases, the poem caused a change in the baby's heart rate. The heart rate accelerated among those who heard their own mother's voice, and decelerated among those who heard a voice other than that of their mother's.
Deceleration of the heart rate is “an attention mechanism (机制)”， Kisilevsky says. The heartbeat among fetuses who heard an unfamiliar voice slowed down, she says, because they were paying close attention to a voice they did not recognize. The fact that the heartbeat changed in both cases — up for Mom, down for someone else — shows the fetuses “noticed both voices”， she says, and could tell one from the other.
By the way, the poem is immaterial here. Kisilevsky suspects she would have had the same results if the mothers had been reading a phone book. “It's not the content that the fetuses recognized，” she says. “We all have our own way of talking. We stop at different times, take breaths at different times, and that's what they are recognizing.”
语篇解读：本文是一篇说明文，主要介绍了一项有关胎儿对声音的识别的研究。 12．What did Kisilevsky's research find? A．Babies are good language learners.
B．Babies' language acquisition begins after birth.
C．Babies can recognize Mom's voice while in the womb. D．Infants are more sensitive to Mom's voice than fetuses. 解析：选C 细节理解题。根据第一段中的“Even before we were born, we knew our mother's voice and could distinguish it from other voices”并结合下文内容可知，我们在出生之前就已经熟悉母亲的声音，并能将其与其他声音区分开来。由此可知，婴儿在母亲的子宫中就能识别母亲的声音。故选C。
13．What led to the change in fetuses' heart rate according to the research?
A．Their familiarity with the voice. B．The quality of the recordings. C．Their curiosity about everything. D．The content of the poem recorded.
解析：选A 细节理解题。根据倒数第二段中的第二句可知，在研究中，胎儿对声音的熟悉度的不同导致了他们心率的变化。故选A。
14．What can be inferred from the last paragraph? A．Adults talk in a way quite different from babies. B．Kisilevsky firmly believes her findings are applicable. C．Speech patterns are what fetuses recognize in telling voices. D．Different experimental materials can lead to different results. 解析：选C 推理判断题。根据最后一段的内容，尤其是最后一句可知，胎儿在辨别声音时识别的是人们的说话方式，即他们的语言模式。故选C。
15．In which column of a newspaper can we read this passage? A．Medicine. C．Education.
B．Lifestyle. D．Science.
解析：选D 文章出处题。通读全文可知，本文主要介绍了一项有关胎儿对声音的识别的研究，它最可能出现在报纸的科学专栏上。故选D。
Ⅱ.阅读七选五
(2020·惠州调研)By 2025, water shortage will be a big problem for about 1.8 billion people. In a world where water resource is increasingly short, nations cannot afford to waste it.__16__ After we use water in our homes and businesses, it is washed away, and takes many valuable resources with it.
Waste water is rich in carbon and nutrients.__17__ A number of nations and major cities have already built waste water treatment plants.They can effectively recover nutrients and bioenergy, and produce “new water” that can be reused.But more than 80% of all waste water still currently flows into natural ecosystems, polluting the environment and taking valuable nutrients and other recoverable materials with it.
__18__ This is still better than the situation in smaller cities.In Latin American countries, those living in small and medium-sized cities at most treat it in the form of septic tanks (化粪池) that lack regular and proper maintenance.
Imagine that outside one of these small cities lies a lovely piece of land: on the surface it is pleasingly built and provides habitats for local wildlife. Beneath the surface is a wetland that treats waste water and produces energy.The energy produced saves families from having to use firewood collected in the wild.This is not a dream project.__19__ A team of scientists have been looking into the potential of constructed wetland environments.Having analyzed 800 examples of biomass in more than 20 countries, they found that, depending on climate and the type of plant used in the construction of this type of wetland, up to 45 hectares of land could be irrigated with waste water.__20__
A．But that is exactly what we do.
B．This can provide easy access to clean water.
C．There is no longer any good reason to waste any type of water. D．A constructed wetland environment is already in practice on a small scale.
E．This would reduce the need for fresh water for irrigation and energy for pumping.
F．If collected and treated properly, it could provide “new water”， fertilizer, and energy.
G．Although waste water systems in large cities are effective, the whole procedure usually costs much.
语篇解读：本文是一篇说明文，主要介绍了当前世界水资源的现状以及有效利用水资源的方法。 16．解析：选A 上文说在水资源短缺的大环境下，很多国家不能承担浪费(的后果)，下文说我们用完水后，就直接把水冲走。根据上下文可知，A项“但是那正是我们所做的”与此处匹配，起承上启下作用，故选A。
17．解析：选F 上文说废水富含碳元素和养分，而F项说如果收集和处理得当，它就能提供“新的水”、肥料和能量，前后形成语义上的衔接，故选F。
18．解析：选G 下文讲述的是拉丁美洲的中小城市的废水处理系统缺乏常规和合适的维护，而G项提到大城市的废水处理系统有效但成本高，与本段内容吻合，故选G。
19．解析：选D 上文提到在这些小城市建造湿地环境的设想，下文提到已经有科学家在研究建造的湿地环境的潜力了，由此可知，D项“建造的湿地环境已经在小范围的实践中了”符合语境。
20．解析：选E 上文讲述的是这种解决方案的另一种好处是人们可以用废水灌溉农田，而E项说这可以减少用淡水灌溉的需求及抽水所需的能量，前后语义衔接，故选E。
练(二) 语言知识运用组块专练 ——练准度 (限时：30分钟) Ⅰ.完形填空
(2020·押题卷四)Earlier this year, I created the Gustine Traveling